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1

Gamma radiation characteristics of plutonium dioxide fuel  

NASA Technical Reports Server (NTRS)

Investigation of plutonium dioxide as an isotopic fuel for Radioisotope Thermoelectric Generators yielded the isotopic composition of production-grade plutonium dioxide fuel, sources of gamma radiation produced by plutonium isotopes, and the gamma flux at the surface.

Gingo, P. J.

1969-01-01

2

An analysis of the impact of having uranium dioxide mixed in with plutonium dioxide  

SciTech Connect

An assessment was performed to show the impact on airborne release fraction, respirable fraction, dose conversion factor and dose consequences of postulated accidents at the Plutonium Finishing Plant involving uranium dioxide rather than plutonium dioxide.

MARUSICH, R.M.

1998-10-21

3

Neutron radiation characteristics of plutonium dioxide fuel  

NASA Technical Reports Server (NTRS)

The major sources of neutrons from plutonium dioxide nuclear fuel are considered in detail. These sources include spontaneous fission of several of the Pu isotopes, (alpha, n) reactions with low Z impurities in the fuel, and (alpha, n) reactions with O-18. For spontaneous fission neutrons a value of (1.95 + or - 0.07) X 1,000 n/s/g PuO2 is obtained. The neutron yield from (alpha, n) reactions with oxygen is calculated by integrating the reaction rate equation over all alpha-particle energies and all center-of-mass angles. The results indicate a neutron emission rate of (1.14 + or - 0.26) X 10,000 n/s/g PuO2. The neutron yield from (alpha, n) reactions with low Z impurities in the fuel is presented in tabular form for one part part per million of each impurity. The total neutron yield due to the combined effects of all the impurities depends upon the fractional weight concentration of each impurity. The total neutron flux emitted from a particular fuel geometry is estimated by adding the neutron yield due to the induced fission to the other neutron sources.

Taherzadeh, M.

1972-01-01

4

Standard specification for sintered (Uranium-Plutonium) dioxide pellets  

E-print Network

1.1 This specification covers finished sintered and ground (uranium-plutonium) dioxide pellets for use in thermal reactors. It applies to uranium-plutonium dioxide pellets containing plutonium additions up to 15 % weight. This specification may not completely cover the requirements for pellets fabricated from weapons-derived plutonium. 1.2 This specification does not include (1) provisions for preventing criticality accidents or (2) requirements for health and safety. Observance of this specification does not relieve the user of the obligation to be aware of and conform to all applicable international, federal, state, and local regulations pertaining to possessing, processing, shipping, or using source or special nuclear material. Examples of U.S. government documents are Code of Federal Regulations Title 10, Part 50Domestic Licensing of Production and Utilization Facilities; Code of Federal Regulations Title 10, Part 71Packaging and Transportation of Radioactive Material; and Code of Federal Regulations Tit...

American Society for Testing and Materials. Philadelphia

2001-01-01

5

Supercritical fluid carbon dioxide cleaning of plutonium parts  

SciTech Connect

Supercritical fluid carbon dioxide is under investigation in this work for use as a cleaning solvent for the final cleaning of plutonium parts. These parts must be free of organic residue to avoid corrosion in the stockpile. Initial studies on stainless steel and full-scale mock-up parts indicate that the oils of interest are easily and adequately cleaned from the metal surfaces with supercritical fluid carbon dioxide. Results from compatibility studies show that undesirable oxidation or other surface reactions are not occurring during exposure of plutonium to the supercritical fluid. Cleaning studies indicate that the oils of interest are removed from the plutonium surface under relatively mild conditions. These studies indicate that supercritical fluid carbon dioxide is a very promising cleaning medium for this application.

Hale, S.J.

1991-12-31

6

THE MICROSTRUCTURE OF PLUTONIUM DIOXIDE PREPARED BY VARIOUS METHODS  

Microsoft Academic Search

The microstructure of plutonium dioxide prepared from the nitrate, ; iodate, suliate, hydroxide, and oxalate was examined. The preparation route has ; a marked influence on physical characteristics, especially on particle size ; distribution surface area and density. The sulfate gives a powder of low ; particle porositv and marked resistance to crystallite growth at higher ; temperatures. The powder

K. E. Francis; R. G. Sowden

1959-01-01

7

PLUTONIUM UPTAKE BY PLANTS FROM SOIL CONTAINING PLUTONIUM-238 DIOXIDE PARTICLES  

EPA Science Inventory

Three plant species--alfalfa, lettuce, and radishes were grown in soils contaminated with plutonium-238 dioxide (238)PuO2 at concentrations of 23, 69, 92, and 342 nanocuries per gram (nCi/g). The length of exposure varied from 60 days for the lettuce and radishes to 358 days for ...

8

Supercritical fluid carbon dioxide cleaning of plutonium parts  

SciTech Connect

Supercritical fluid (SCF) carbon dioxide (CO{sub 2}) is being evaluated for use as a cleaning solvent to replace 1,1,1-trichloroethane for the final cleaning of plutonium (Pu) parts. These parts must be free of organic residue to avoid corrosion in the stockpile. Thermodynamic and kinetic data for selected reactions of Pu metal are evaluated as a basis for assessing the risk of a violent exothermic reaction during the use of SCF CO{sub 2} on Pu. The need for considering kinetic behavior of a reaction in assessing its thermal risk is demonstrated. Weight difference data and results of xray photoelectron spectroscopy to evaluate the surface after exposure to the supercritical fluid show that SCF CO{sub 2} is an effective and compatible cleaning solvent.

Hale, S.J.; Haschke, J.M.; Cox, L.E.

1993-09-01

9

Hydrogen yields from water on the surface of plutonium dioxide  

NASA Astrophysics Data System (ADS)

The long term storage of separated plutonium dioxide (PuO2) in sealed canisters requires an understanding of the processes occurring within the cans. This includes potential mechanisms that lead to can pressurisation, including the radiolysis of adsorbed water forming hydrogen. New measurements of H2 production rates from three sources of PuO2 show low rates at low water monolayer coverage but a sharp increase between 75% and 95% relative humidity. This behaviour being quite different to that reported for CeO2 and UO2, which, therefore, cannot be considered as suitable analogues for PuO2/H2O radiation chemistry. It is concluded that surface recombination reactions are likely to be important in the radiation chemistry and that the H2 production arises from a radiolytic process and not a thermal reaction, at least in these experiments.

Sims, Howard E.; Webb, Kevin J.; Brown, Jamie; Morris, Darrell; Taylor, Robin J.

2013-06-01

10

Emitted radiation characteristics of plutonium dioxide radioisotope thermoelectric generators  

NASA Technical Reports Server (NTRS)

The nuclear and emitted radiation characteristics of the radioisotope elements and impurities in commercial grade plutonium dioxide are presented in detail. The development of the methods of analysis are presented. Radioisotope thermoelectric generators (RTG) of 1575, 3468 and 5679 thermal watts are characterized with respect to neutron and gamma photon source strength as well as spatial and number flux distribution. The results are presented as a function of detector position and light element contamination concentration for fuel age ranging from 'fresh' to 18 years. The data may be used to obtain results for given O-18 and Pu-236 concentrations. The neutron and gamma photon flux and dose calculations compare favorably with reported experimental values for SNAP-27.

Gingo, P. J.; Steyn, J. J.

1971-01-01

11

Plutonium dioxide storage: Conditions for preparation and handling  

SciTech Connect

Desorption and adsorption of plutonium dioxide are derived from production-scale experiments that demonstrate techniques of preparing weapons-grade material for extended storage. In combination with data from literature, results define conditions for preparing and certifying PuO{sub 2} and provide essential information for developing and implementing a repackaging process compliant with DOE standards for safe storage of plutonium. As demonstrated by loss-on-ignition (LOI) analysis, adsorbates are effectively removed by heating the oxide in air at 950 C for two hours. After oxides are fired at this temperature, specific surface areas are consistently less than 5 m{sup 2}/g. Due to this low surface area, water adsorption by fired oxide is limited to a maximum of 0.2 mass % at 50% relative humidity. Kinetic data for the adsorption process show that water is accommodated on the oxide surface by a sequence of distinct first-order steps comprising five types of adsorbate interaction and accumulating ten molecular layers of H{sub 2}0 at 100% humidity. An equation defining the humidity dependence of the adsorption rate during the first step is applied in estimating time periods that a fired oxide may remain in given configurations without detrimental adsorption. Particle size measurements show that the source terms for environmental dispersal of oxides prepared by hydride-catalyzed reaction of metal and by oxalate calcination are approximately 20 and 0.1 mass %, respectively, and that the values are reduced by firing. Evidence for a chemical reaction between dioxide and water is discussed and practical applications of the results to oxide stabilization and LOI analysis are presented.

Haschke, J.M.; Ricketts, T.E.

1995-08-01

12

The plutonium\\/hydrogen reaction: The pressure dependence of reaction initiation time and nucleation rate controlled by a plutonium dioxide over-layer  

Microsoft Academic Search

As part of an ongoing programme to quantify those parameters which influence the early stages of the plutonium hydriding reaction, the hydrogen pressure dependence of both plutonium hydriding initiation time (It) and hydriding nucleation rate (Nr) have been determined for plutonium covered in a reproducible dioxide over-layer. The data show that initiation time is inversely proportional to hydrogen pressure, while

Gordon W. McGillivray; John P. Knowles; Ian M. Findlay; Marina J. Dawes

2011-01-01

13

Reactions of plutonium dioxide with water and oxygen-hydrogen mixtures: Mechanisms for corrosion of uranium and plutonium  

SciTech Connect

Investigation of the interactions of plutonium dioxide with water vapor and with an oxygen-hydrogen mixture show that the oxide is both chemically reactive and catalytically active. Correspondence of the chemical behavior with that for oxidation of uranium in moist air suggests that similar catalytic processes participate in the mechanism of moisture-enhanced corrosion of uranium and plutonium. Evaluation of chemical and kinetic data for corrosion of the metals leads to a comprehensive mechanism for corrosion in dry air, water vapor, and moist air. Results are applied in confirming that the corrosion rate of Pu in water vapor decreases sharply between 100 and 200 degrees C.

Haschke, John M.; Allen, Thomas H.; Morales, Luis A.

1999-06-18

14

Sonochemical Digestion of High-Fired Plutonium Dioxide Samples  

SciTech Connect

This work was performed as part of a broader effort to automate analytical methods for determining plutonium and other radioisotopes in environmental samples. The work described here represented a screening study to evaluate the effect of applying ultrasonic irradiation to dissolve high-fired plutonium oxide. The major findings of this work can be summarized as follows: (1) High-fired plutonium oxide does not undergo measurable dissolution when sonicated in nitric acid solutions, even at a high concentration range of nitric acid where the calculated thermodynamic solubility of plutonium oxide exceeds the ?g/mL level. (2) Applying organic complexants (nitrilotriacetic acid) and reductants (hydroxyurea) in 1.5 M nitric acid does not significantly increase the dissolution compared with digestion in nitric acid alone. Nearly all (99.5%) of the plutonium oxide remains undissolved under these conditions. (3) The action of a strong inorganic reductant, titanium trichloride in 25 wt% HCl, results in 40% dissolution of the plutonium oxide when the titanium trichloride concentration is ?1 wt% under sonication. (4) Oxidative treatment of plutonium oxide by freshly dissolved AgO ({approx}20 mg/mL) in 1.5 M nitric acid with sonication resulted in 95% plutonium oxide dissolution. However, the same treatment of plutonium oxide mechanically mixed with 50 mg of Columbia River sediment (CRS) results in a significant decrease of dissolution yield of plutonium oxide (<20% dissolved at the same AgO loading) because of parasitic consumption of AG(II) by oxidizable components of the CRS. (5) Digesting plutonium oxide in HF resulted in dissolution yields slightly higher than 80% for HF concentration from 6 M to 14 M. Sonication did not result in any improvement in dissolution efficiency in HF. (6) Mixed nitric acid/HF solutions result in a higher dissolution yield of plutonium oxide compared with digestion in HF alone (at the same HF concentrations). Practically quantitative dissolution of PuO2 can be achieved with 6 to 8 M nitric acid + 14 M HF or 8 M nitric acid + 4 M HF mixtures. In the latter case, quantitative dissolution of plutonium oxide was demonstrated only with sonication. Overall, the results indicate that applying ultrasound in an isolated cup horn configuration to dissolve refractory plutonium oxide does not offer any substantial advantage over conventional ?heat and mix? treatment. Oxidative treatment by AgO appears to be effective only when very little or no oxidizable materials are present in the digested sample. The catalytic use of Ag(II) in the ''Catalyzed Electrolytic Plutonium Oxide Dissolution'' technology would probably be more effective than using AgO because the Ag(II) is continually regenerated electrochemically. Reductive treatment with titanium trichloride in HCl solution proves to be less efficient than the previously observed effect based on in situ generation of Ti(III) in phosphoric acid and sulfuric acid media using a dip probe sonication setup. The previous experiments, however, were performed at higher temperature and with non-steady concentration profiles of Ti(III) ion in the process of sonochemical digestion.

Sinkov, Sergei I.; Lumetta, Gregg J.

2006-10-12

15

Further comments on the induction of lung tumors by plutonium dioxide in beagles.  

PubMed

A series of recent papers describes the final results obtained from studies of the effects of inhaled plutonium dioxide on beagle dogs. This note considers the value of a microdosimetric assessment of these data. In particular, it offers support for the existence of a threshold for the induction of lung tumors. PMID:22420023

Simmons, J A; Richards, S R

2012-03-01

16

Vapor pressures and vapor compositions in equilibrium with hypostoichiometric plutonium dioxide at high temperatures  

Microsoft Academic Search

Vapor pressures and vapor compositions in equilibrium with a hypostoichiometric plutonium dioxide condensed phase have been calculated for the temperature range 1500 less than or equal to T less than or equal to 4000 K. Thermodynamic functions for the condensed phase and for each of the gaseous species were combined with an oxygen-potential model, which has been extended from the

D. W. Green; J. K. Fink; L. Leibowitz

1983-01-01

17

Toxicity of inhaled plutonium dioxide in beagle dogs  

SciTech Connect

This study was conducted to determine the biological effects of inhaled {sup 238}PuO{sub 2} over the life spans of 144 beagle dogs. The dogs inhaled one of two sizes of monodisperse aerosols of {sup 238}PuO{sub 2} to achieve graded levels of initial lung burden (ILB). The aerosols also contained {sup 169}Yb to provide a {gamma}-ray-emitting label for the {sup 238}Pu inhaled by each dog. Excreta were collected periodically over each dog`s life span to estimate plutonium excretion; at death, the tissues were analyzed radiochemically for plutonium activity. The tissue content and the amount of plutonium excreted were used to estimate the ILB. These data for each dog were used in a dosimetry model to estimate the ILB. These data for each dog were used in a dosimetry model to estimate tissue doses. The lung, skeleton and liver received the highest {alpha}-particle doses, ranging from 0.16-68 Gy for the liver. At death, all dogs were necropsied, and all organs and lesions were sampled and examined by histopathology. Findings of non-neoplastic changes included neutropenia and lymphopenia that developed in a dose-related fashion soon after inhalation exposure. These effects persisted for up to 5 years in some animals, but no other health effects could be related to the blood changes observed. Radiation pneumonitis was observed among the dogs with the highest ILBs. Deaths from radiation pneumonitis occurred from 1.5 to 5.4 years after exposure. Tumors of the lung, skeleton and liver occurred beginning at about 3 years after exposure. These findings in dogs suggest that similar dose-related biological effects could be expected in humans accidentally exposed to {sup 238}PuO{sub 2}. 89 refs., 10 figs., 11 tab.

Muggenburg, M.A.; Guilmette, R.A.; Mewhinney, J.A. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States)] [and others

1996-03-01

18

Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets  

E-print Network

1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade plutonium dioxide powders and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Plutonium Sample Handling 8 to 10 Plutonium by Controlled-Potential Coulometry Plutonium by Ceric Sulfate Titration Plutonium by Amperometric Titration with Iron(II) Plutonium by Diode Array Spectrophotometry Nitrogen by Distillation Spectrophotometry Using Nessler Reagent 11 to 18 Carbon (Total) by Direct Combustion–Thermal Conductivity 19 to 30 Total Chlorine and Fluorine by Pyrohydrolysis 31 to 38 Sulfur by Distillation Spectrophotometry 39 to 47 Plutonium Isotopic Analysis by Mass Spectrometry Rare Earth Elements by Spectroscopy 48 to 55 Trace Elements by Carrier–Distillation Spectroscopy 56 to 63 Impurities by ICP-AES Impurity Elements by Spark-Source Mass Spectrography 64 to 70 Moisture by the Coulomet...

American Society for Testing and Materials. Philadelphia

2010-01-01

19

Dissolution of plutonium dioxide using HCl-HF  

SciTech Connect

High-fired PuO/sub 2/ (950/sup 0/ to 1700/sup 0/C) can be dissolved in boiling 6.1 M HCl when the fluoride ion concentration to plutonium mole (F/sup -//Pu) ratio is >0.5. The amount of PuO/sub 2/ (950/sup 0/C calcined oxide) dissolved in 1 hour increased from approx.0.2% to 66%, 91%, and 100% as the F/sup -//Pu ratio increased from 0 to 0.5, 1.0, and 1.8, respectively. The PuO/sub 2/ dissolution rates in HCl-CaF/sub 2/ solutions decrease with increasing oxide calcination temperatures and decreasing oxide surface areas. At a F/sup -//Pu ratio of 1.8, the 1700/sup 0/C calcined oxide was completely dissolved in 2.5 hours versus 1 hour for the 950/sup 0/C calcined oxide.

Bray, L.A.; Ryan, J.L.; Wheelwright, E.J.

1986-10-01

20

Primary pulmonary sarcoma in a rhesus monkey after inhalation of plutonium dioxide  

SciTech Connect

A pulmonary fibrosarcoma of bronchial origin was discovered in a Rhesus monkey that died of pulmonary fibrosis 9 years after inhalation of plutonium-239 dioxide and with a radiation dose to lung of 1400 rad (14 Gy). It grew around the major bronchus of the right cardiac lung lobe and extended into the bronchial lumen and into surrounding pulmonary parenchyma. It also readily invaded muscular pulmonary arteries, resulting in infarction and scarring in the right cardiac lobe. Despite this aggressive growth, the tumor did not metastasize. The primary cause of death was severe pulmonary fibrosis involving the alveolar septa and and perivascular and peribronchial interstitium. Bullous or pericitrical emphysema was prominent. The initial lung burden of plutonium in this monkey was 270 nCi (10 kBq) which is equivalent to approximately 500 times the maximum permissible lung burden for man on a radioactivity per unit body weight basis. The time-dose relationship for survival is consistent with that of dogs and baboons that inhaled plutonium dioxide and died with lung tumors.

Hahn, F.F.; Brooks, A.L.; Mewhinney, J.A.

1987-11-01

21

The plutonium/hydrogen reaction: The pressure dependence of reaction initiation time and nucleation rate controlled by a plutonium dioxide over-layer  

NASA Astrophysics Data System (ADS)

As part of an ongoing programme to quantify those parameters which influence the early stages of the plutonium hydriding reaction, the hydrogen pressure dependence of both plutonium hydriding initiation time ( I t) and hydriding nucleation rate ( N r) have been determined for plutonium covered in a reproducible dioxide over-layer. The data show that initiation time is inversely proportional to hydrogen pressure, while nucleation rate is proportional to hydrogen pressure. Both observations are consistent with a model of hydriding attack in which the dioxide over-layer acts as a diffusion barrier, controlling the flow of hydrogen from the gas phase to the oxide/metal interface. The low scatter and reproducibility of the experimental data set demonstrate the importance of synthesising well controlled and characterised oxide layers prior to determining these experimental parameters.

McGillivray, Gordon W.; Knowles, John P.; Findlay, Ian M.; Dawes, Marina J.

2011-05-01

22

The effect of plutonium dioxide water surface coverage on the generation of hydrogen and oxygen  

SciTech Connect

The conditions for the production of oxygen during radiolysis of water adsorbed onto plutonium dioxide powder are discussed. Studies in the literature investigating the radiolysis of water show that both oxygen and hydrogen can be generated from water adsorbed on high-purity plutonium dioxide powder. These studies indicate that there is a threshold in the amount of water below which oxygen is not generated. The threshold is associated with the number of monolayers of adsorbed water and is shown to occur at approximately two monolayers of molecularly adsorbed water. Material in equilibrium with 50% relative humidity (RH) will be at the threshold for oxygen generation. Using two monolayers of molecularly adsorbed water as the threshold for oxygen production, the total pressure under various conditions is calculated assuming stoichiometric production of hydrogen and oxygen. The specific surface area of the oxide has a strong effect on the final partial pressure. The specific surface areas resulting in the highest pressures within a 3013 container are evaluated. The potential for oxygen generation is mitigated by reduced relative humidity, and hence moisture adsorption, at the oxide surface which occurs if the oxide is warmer than the ambient air. The potential for oxygen generation approaches zero as the temperature difference between the ambient air and the material approaches 6 C.

Veirs, Douglas K. [Los Alamos National Laboratory; Berg, John M. [Los Alamos National Laboratory; Crowder, Mark L. [Savannah River National Laboratory

2012-06-20

23

Ground state properties and high pressure behavior of plutonium dioxide: Systematic density functional calculations  

E-print Network

Plutonium dioxide is of high technological importance in nuclear fuel cycle and is particularly crucial in long-term storage of Pu-based radioactive waste. Using first-principles density-functional theory, in this paper we systematically study the structural, electronic, mechanical, thermodynamic properties, and pressure induced structural transition of PuO$_{2}$. To properly describe the strong correlation in the Pu $5f$ electrons, the local density approximation$+U$ and the generalized gradient approximation$+U$ theoretical formalisms have been employed. We optimize the $U$ parameter in calculating the total energy, lattice parameters, and bulk modulus at the nonmagnetic, ferromagnetic, and antiferromagnetic configurations for both ground state fluorite structure and high pressure cotunnite structure. The best agreement with experiments is obtained by tuning the effective Hubbard parameter $U$ at around 4 eV within the LDA$+U$ approach. After carefully testing the validity of the ground state, we further in...

Zhang, Ping; Zhao, Xian-Geng

2010-01-01

24

Plutonium  

NASA Astrophysics Data System (ADS)

The element plutonium occupies a unique place in the history of chemistry, physics, technology, and international relations. After the initial discovery based on submicrogram amounts, it is now generated by transmutation of uranium in nuclear reactors on a large scale, and has been separated in ton quantities in large industrial facilities. The intense interest in plutonium resulted fromthe dual-use scenario of domestic power production and nuclear weapons - drawing energy from an atomic nucleus that can produce a factor of millions in energy output relative to chemical energy sources. Indeed, within 5 years of its original synthesis, the primary use of plutonium was for the release of nuclear energy in weapons of unprecedented power, and it seemed that the new element might lead the human race to the brink of self-annihilation. Instead, it has forced the human race to govern itself without resorting to nuclear war over the past 60 years. Plutonium evokes the entire gamut of human emotions, from good to evil, from hope to despair, from the salvation of humanity to its utter destruction. There is no other element in the periodic table that has had such a profound impact on the consciousness of mankind.

Clark, David L.; Hecker, Siegfried S.; Jarvinen, Gordon D.; Neu, Mary P.

25

Ground-state properties and high-pressure behavior of plutonium dioxide: Density functional theory calculations  

NASA Astrophysics Data System (ADS)

Plutonium dioxide is of high technological importance in nuclear fuel cycle and is particularly crucial in long-term storage of Pu-based radioactive waste. Using first-principles density-functional theory, in this paper we systematically study the structural, electronic, mechanical, thermodynamic properties, and pressure-induced structural transition of PuO2 . To properly describe the strong correlation in Pu5f electrons, the local-density approximation (LDA)+U and the generalized gradient approximation+U theoretical formalisms have been employed. We optimize U parameter in calculating the total energy, lattice parameters, and bulk modulus at nonmagnetic, ferromagnetic, and antiferromagnetic configurations for both ground-state fluorite structure and high-pressure cotunnite structure. Best agreement with experiments is obtained by tuning the effective Hubbard parameter U at around 4 eV within LDA+U approach. After carefully testing the validity of the ground-state calculation, we further investigate the bonding nature, elastic constants, various moduli, Debye temperature, hardness, ideal tensile strength, and phonon dispersion for fluorite PuO2 . Some thermodynamic properties, e.g., Gibbs free energy, volume thermal expansion, and specific heat are also calculated. As for cotunnite phase, besides elastic constants, various moduli, and Debye temperature at 0 GPa, we have further presented our calculated electronic, structural, and magnetic properties for PuO2 under pressure up to 280 GPa. A metallic transition at around 133 GPa and an isostructural transition in pressure range of 75-133 GPa are predicted. Additionally, as an illustration on the valency trend and subsequent effect on the mechanical properties, the calculated results for other actinide metal dioxides ( ThO2 , UO2 , and NpO2 ) are also presented.

Zhang, Ping; Wang, Bao-Tian; Zhao, Xian-Geng

2010-10-01

26

Two convenient low-temperature routes to single crystals of plutonium dioxide  

NASA Astrophysics Data System (ADS)

During the solvothermal synthesis of a low-dimensional borate, KB5O7(OH)2?2H2O, in the presence of Pu(III), single crystals of plutonium dioxide unexpectedly formed. Single crystals of PuO2 also formed during the hydrothermal synthesis of another borate, Na2B5O8(OH)?2H2O, in the presence of Pu(III). The reactions were conducted at 170 °C and 150 °C, respectively, which are much lower temperature than previously reported preparations of crystalline PuO2. Yellow-green crystals with a tablet habit were characterized by single crystal X-ray diffraction and solid-state UV-vis-NIR absorption spectroscopy. The crystal structure was solved by direct methods with R1 = 1.26% for 19 unique observed reflections. PuO2 is cubic, space group Fm3?m, and adopts the fluorite structure type. The lattice parameter was determined to be a = 5.421(5) Å giving a volume of 159.3(2) Å3. The absorption spectrum is consistent with Pu(IV).

Meredith, Nathan A.; Wang, Shuao; Diwu, Juan; Albrecht-Schmitt, Thomas E.

2014-11-01

27

Vapor pressures and vapor compositions in equilibrium with hypostoichiometric uranium-plutonium dioxide at high temperatures  

SciTech Connect

Vapor pressures and vapor compositions in equilibrium with a hypostoichiometric uranium-plutonium dioxide condensed phase (U/sub 1-y/Pu/sub y/)O/sub 2-x/, as functions of T, x, and y, have been calculated for 0.0 less than or equal to x less than or equal to 0.1, 0.0 less than or equal to y less than or equal to 0.3, and for the temperature range 2500 less than or equal to T less than or equal to 6000 K. The range of compositions and temperatures was limited to the region of interest to reactor safety analysis. Thermodynamic functions for the condensed phase and for each of the gaseous species were combined with an oxygen potential model to obtain partial pressures of O, O/sub 2/, Pu, PuO, PuO/sub 2/, U, UO, UO/sub 2/, and UO/sub 3/ as functions of T, x, and y.

Green, D.W.; Fink, J.K.; Leibowitz, L.

1982-01-01

28

A kinetic study of plutonium dioxide dissolution in hydrochloric acid using iron (II) as an electron transfer catalyst  

SciTech Connect

Effective dissolution of plutonium dioxide has traditionally been accomplished by contact with strong nitric acid containing a small amount of fluoride at temperatures of {approximately} 100 C. In spite of these aggressive conditions, PuO{sub 2} dissolution is sometimes incomplete requiring additional contact with the solvent. This work focused on an alternative to conventional dissolution in nitric acid where an electron transfer catalyst, Fe(II), was used in hydrochloric acid. Cyclic voltammetry was employed as an in-situ analytical technique for monitoring the dissolution reaction rate. The plutonium oxide selected for this study was decomposed plutonium oxalate with > 95% of the material having a particle diameter (< 70 {micro}m) as determined by a scanning laser microscopy technique. Attempts to dry sieve the oxide into narrow size fractions prior to dissolution in the HCl-Fe(II) solvent system failed, apparently due to significant interparticle attractive forces. Although sieve splits were obtained, subsequent scanning laser microscopy analysis of the sieve fractions indicated that particle segregation was not accomplished and the individual sieve fractions retained a particle size distribution very similar to the original powder assemblage. This phenomena was confirmed through subsequent dissolution experiments on the various screen fractions which illustrated no difference in kinetic behavior between the original oxide assemblage and the sieve fractions.

Fife, K.W.

1996-09-01

29

Interactions of Plutonium Dioxide with Water and Oxygen-Hydrogen Mixtures  

SciTech Connect

Pressure-volume-temperature data and mass spectrometric results obtained during exposure of PuO{sub 2} to D{sub 2}O show that the dioxide reacts with water at room temperature to produce a higher oxide (PuO{sub 2+x})and H{sub 2}. Results demonstrate that PuO{sub 2+x} is the thermodynamically stable oxide in air. The absence of O{sub 2} at detectable levels in the gas phase implies that radiolytic decomposition of water to the elements is not a significant reaction. The rate of the PuO{sub 2}+H{sub 2}O reaction is 6{+-}4 nmol H{sub 2}/m{sup 2} day, a value that is independent of the H{sub 2}O concentration on the oxide over a range that extends from fractional monolayer coverage to saturation by liquid water. Evaluation of literature data shows that oxide compositions in excess of PuO{sub 2.25} are attained, but the maximum value of x is unknown. During exposure of PuO{sub 2} to a 2:1 D{sub 2}:O{sub 2} mixture at room temperature, the elements combine by a process consistent with a surface-catalyzed reaction. Water is simultaneously formed by the H{sub 2}+O{sub 2} reaction and consumed by the PuO{sub 2} + H{sub 2}O reaction and accumulates until the opposing rates are equal. Thereafter, PuO{sub 2+x} is formed at a constant rate by the water-catalyzed PuO{sub 2} + O{sub 2} reaction. The failure of earlier attempts to prepare higher oxides of plutonium is discussed and the catalytic cycle that promotes the reaction of PuO{sub 2} with O{sub 2} is described. Implications of the results for extended storage and environmental chemistry of oxide are examined. Moisture-catalyzed oxidation of PuO{sub 2} accounts for observation of both pressure increases and decreases in oxide storage containers with air atmospheres. Application of the experimental rate results indicates that the reaction of a typical oxide with 0.5 mass % of adsorbed water maybe complete after 25 to 50 years at room temperature.

Haschke, J.M.; Allen, T.H.

1999-01-01

30

On the melting behaviour of uranium/plutonium mixed dioxides with high-Pu content: A laser heating study  

NASA Astrophysics Data System (ADS)

The melting behaviour of mixed uranium-plutonium dioxides (MOX) has been investigated by laser heating under controlled atmosphere in the PuO 2-rich composition range (with amount-of-substance fraction x(PuO 2) ?75%). The observed solidus/liquidus points are in agreement with the newly measured melting point of pure plutonium dioxide (3017 K). They suggest the existence of a minimum freezing temperature at a composition x(PuO 2) between 50% and 80%, in contrast with earlier research carried out with traditional furnace heating methods. The current results have been obtained under optimised experimental conditions aimed at maintaining the integrity and original composition of the samples throughout the laser heating cycles. With this goal in mind, experiments have been carried out under controlled gas pressure (pressurised air or argon) and short time duration (<0.25 s). A critical discussion of the present results highlights the fact that the formation of the gas phase has to be taken into account in the study of the high-Pu MOX behaviour at high temperature. The experimental results obtained thus correspond to slightly hypo-stoichiometric (U, Pu)O 2-x compositions in equilibrium with the gas phase.

De Bruycker, F.; Boboridis, K.; Konings, R. J. M.; Rini, M.; Eloirdi, R.; Guéneau, C.; Dupin, N.; Manara, D.

2011-12-01

31

Dynamic shape factors for hydox-generated plutonium dioxide-type non-sperical objects  

E-print Network

. New York: John Wiley and Sons; 1986 Department of Energy. Surplus plutonium disposition draft environmental impact statement, volume 1, part A. New York NY; 1998 Fuchs, N. The mechanics of aerosols. New York: Dover Publications; 1964 Griffiths, W...

Lohaus, James Harold

1999-01-01

32

Theory of valence-band and core-level photoemission from plutonium dioxide  

NASA Astrophysics Data System (ADS)

The correlated-band theory implemented as a combination of the local-density approximation with the dynamical mean-field theory is applied to PuO2. An insulating electronic structure, consistent with the experimental valence-band photoemission spectra, is obtained. The calculations yield a nonmagnetic ground state that is characterized by a noninteger filling of the plutonium 5f shell. The noninteger filling as well as the satellites appearing in the 4f core-level photoemission spectra originate in a sizable hybridization of the 5f shell with the 2p states of oxygen.

Koloren?, Jind?ich; Kozub, Agnieszka L.; Shick, Alexander B.

2015-03-01

33

A novel analytical method for the determination of residual moisture in plutonium dioxide: Supercritical fluid extraction/Fourier transform infrared spectroscopy  

SciTech Connect

A novel approach has been developed at the Los Alamos National Laboratory for the quantitative determination of moisture content in impure plutonium oxide. The method combines a commercial supercritical fluid extraction instrument using supercritical carbon dioxide (SCCO{sub 2}) with on-line detection using a high-pressure Fourier Transform Infrared Spectroscopy (FTIR) cell. The combined SCCO{sub 2}/FTIR system has been modified for use inside a fully enclosed glove box. A series of validation experiments were performed using a pure, surrogate oxide (ThO{sub 2}) and an inorganic hydrate (CaSO{sub 4}{center_dot}2H{sub 2}O). The level of agreement between LOI and SCCO{sub 2}/FTIR for the surrogate oxide is excellent. The results for the inorganic hydrate showed excellent correlation with the known amount of water present. Results obtained for a group of nominally pure PuO{sub 2} samples were verified by independent measurement. The results of SCCO{sub 2}/FTIR for impure PuO{sub 2} samples is consistently lower than the results of obtained from the current analytical method (Loss On Ignition), indicating that the current method is inadequate for analytical purposes. While further verification experiments of the SCCO{sub 2}/FTIR method are underway, these initial results suggest that SCCO{sub 2}/FTIR could be used as an alternative analytical method for the Materials Identification and Surveillance program.

Martinez, A.M.; Hollis, W.K.; Rubin, J.B.; Taylor, C.M.V.; Jasperson, M.N.; Vance, D.E.; Rodriguez, J.B.

1999-02-01

34

Alternative technical summary report for direct disposition in deep boreholes: Direct disposal of plutonium metal/plutonium dioxide in compound canisters, Version 4.0. Fissile Materials Disposition Program  

SciTech Connect

This report summarizes and compares the Immobilized and Direct Beep Borehole Disposition Alternatives. The important design concepts, facility features and operational procedures are briefly described, and a discussion of the issues that affect the evaluation of each alternative against the programmatic assessment criteria that have been established for selecting the preferred alternatives for plutonium disposition.

Wijesinghe, A.M.

1996-08-23

35

Pressure dependence of extraction behavior of plutonium(IV) and uranium(VI) from nitric acid solution to supercritical carbon dioxide containing tributylphosphate  

Microsoft Academic Search

Plutonium(IV) and uranium(VI) were extracted into supercritical CO2 fluid phase (SF-CO2) containing tributylphosphate (TBP) with equilibrium distribution ratios, D, e. g., DPu(IV) = 3.1 and DU(IV) = 2.0, for the extraction of 2 × 10?3 M Pu(IV) and U(VI) from 3 M HNO3 into SF-CO2 containing 0.3 M TBP at 60 °C and 15 MPa. A simple linear relation between

Shuichi Iso; Seiichiro Uno; Yoshihiro Meguro; Takayuki Sasaki; Zenko Yoshida

2000-01-01

36

Plutonium aging  

SciTech Connect

The author describes the plutonium aging program at the Los Alamos National Laboratory. The aging of plutonium components in the US nuclear weapons stockpile has become a concern due to several events: the end of the cold war, the cessation of full scale underground nuclear testing as a result of the Comprehensive Test Ban Treaty (CTBT) and the closure of the Rocky Flats Plant--the site where the plutonium components were manufactured. As a result, service lifetimes for nuclear weapons have been lengthened. Dr. Olivas will present a brief primer on the metallurgy of plutonium, and will then describe the technical approach to ascertaining the long-term changes that may be attributable to self-radiation damage. Facilities and experimental techniques which are in use to study aging will be described. Some preliminary results will also be presented.

Olivas, J.D.

1999-03-01

37

Fissile Material Disposition Program: Deep Borehole Disposal Facility PEIS data input report for direct disposal. Direct disposal of plutonium metal/plutonium dioxide in compound metal canisters. Version 3.0  

SciTech Connect

The US Department of Energy (DOE) is examining options for disposing of excess weapons-usable nuclear materials [principally plutonium (Pu) and highly enriched uranium (HEU)] in a form or condition that is substantially and inherently more difficult to recover and reuse in weapons production. This report is the data input report for the Programmatic Environmental Impact Statement (PEIS). The PEIS examines the environmental, safety, and health impacts of implementing each disposition alternative on land use, facility operations, and site infrastructure; air quality and noise; water, geology, and soils; biotic, cultural, and paleontological resources; socioeconomics; human health; normal operations and facility accidents; waste management; and transportation. This data report is prepared to assist in estimating the environmental effects associated with the construction and operation of a Deep Borehole Disposal Facility, an alternative currently included in the PEIS. The facility projects under consideration are, not site specific. This report therefore concentrates on environmental, safety, and health impacts at a generic site appropriate for siting a Deep Borehole Disposal Facility.

Wijesinghe, A.M.; Shaffer, R.J.

1996-01-15

38

Plutonium story  

SciTech Connect

The first nuclear synthesis and identification (i.e., the discovery) of the synthetic transuranium element plutonium (isotope /sup 238/Pu) and the demonstration of its fissionability with slow neutrons (isotope /sup 239/Pu) took place at the University of California, Berkeley, through the use of the 60-inch and 37-inch cyclotrons, in late 1940 and early 1941. This led to the development of industrial scale methods in secret work centered at the University of Chicago's Metallurgical Laboratory and the application of these methods to industrial scale production, at manufacturing plants in Tennessee and Washington, during the World War II years 1942 to 1945. The chemical properties of plutonium, needed to devise the procedures for its industrial scale production, were studied by tracer and ultramicrochemical methods during this period on an extraordinarily urgent basis. This work, and subsequent investigations on a worldwide basis, have made the properties of plutonium very well known. Its well studied electronic structure and chemical properties give it a very interesting position in the actinide series of inner transition elements.

Seaborg, G T

1981-09-01

39

Seaborg's Plutonium ?  

E-print Network

Passive x-ray and gamma-ray analysis was performed on UC Berkeley's EH&S Sample S338. The object was found to contain Pu-239 and no other radioactive isotopes. The mass of Pu-239 contained in this object was determined to be 2.0 +- 0.3 micrograms. These observations are consistent with the identification of this object being the 2.77-microgram plutonium oxide sample described by Glenn Seaborg and his collaborators as the first sample of Pu-239 that was large enough to be weighed.

Norman, Eric B; Telhami, Kristina E

2014-01-01

40

Seaborg's Plutonium?  

E-print Network

Passive x-ray and gamma-ray analysis was performed on UC Berkeley's EH&S Sample S338. The object was found to contain Pu-239 and no other radioactive isotopes. The mass of Pu-239 contained in this object was determined to be 2.0 +- 0.3 micrograms. These observations are consistent with the identification of this object being the 2.77-microgram plutonium oxide sample described by Glenn Seaborg and his collaborators as the first sample of Pu-239 that was large enough to be weighed.

Eric B. Norman; Keenan J. Thomas; Kristina E. Telhami

2015-02-17

41

PROGRESS REPORT. IMPROVED RADIATION DOSIMETRY/RISK ESTIMATES TO FACILITATE ENVIRONMENTAL MANAGEMENT OF PLUTONIUM CONTAMINATED SITES  

EPA Science Inventory

The main objective of this project is to improve capabilities for evaluating health risks to humans associated with inhaling plutonium (Pu). Two key DOE issues are being addressed: (1) the need to improve capabilities for evaluating plutonium dioxide (PuO2)-associated health risk...

42

The plutonium\\/hydrogen reaction: The pressure dependence of reaction initiation time  

Microsoft Academic Search

The hydrogen pressure dependence of the initiation time (It) of the plutonium hydriding reaction has been determined over a hydrogen pressure range of 10–1000mbar for plutonium covered in a dioxide over-layer. The data show that hydriding initiation time is inversely proportional to hydrogen pressure. This observation is consistent with a model of hydriding attack in which the dioxide over-layer acts

Gordon W. McGillivray; John P. Knowles; Ian M. Findlay; Marina J. Dawes

2009-01-01

43

Standard test method for plutonium by Iron (II)/Chromium (VI) amperometric titration  

E-print Network

1.1 This test method covers the determination of plutonium in unirradiated nuclear-grade plutonium dioxide, uranium-plutonium mixed oxides with uranium (U)/plutonium (Pu) ratios up to 21, plutonium metal, and plutonium nitrate solutions. Optimum quantities of plutonium to measure are 7 to 15 mg. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

American Society for Testing and Materials. Philadelphia

2002-01-01

44

North Korean Plutonium Production  

Microsoft Academic Search

In 1992, as part of its obligations under the Nuclear Non?Proliferation Treaty, North Korea declared that it had earlier separated abut 100 grams of plutonium from damaged fuel rods removed from a 25 megawatt?thermal (MWt) gas?graphite reactor at Yongbyon. The plutonium was separated at the nearby “Radiochemical Laboratory.” Separated plutonium is the raw ingredient for making nuclear weapons, but 100

David Albright

1994-01-01

45

Redox speciation of plutonium  

Microsoft Academic Search

Knowledge of the oxidation state distribution of plutonium in natural waters is necessary in modeling its behavior in environmental systems. The redox speciation of plutonium is complicated by such effects as hydrolysis, complexation, disproportionation, solubility, and redox interchange reactions. The insolubility of Pu(OH)4 is often the limiting factor of the net solubility of plutonium in oxic natural waters where Pu(V)O

G. R. Choppin; A. H. Bond; P. M. Hromadka

1997-01-01

46

Conceptual Design for the Pilot-Scale Plutonium Oxide Processing Unit in the Radiochemical Processing Laboratory  

SciTech Connect

This report describes a conceptual design for a pilot-scale capability to produce plutonium oxide for use as exercise and reference materials, and for use in identifying and validating nuclear forensics signatures associated with plutonium production. This capability is referred to as the Pilot-scale Plutonium oxide Processing Unit (P3U), and it will be located in the Radiochemical Processing Laboratory at the Pacific Northwest National Laboratory. The key unit operations are described, including plutonium dioxide (PuO2) dissolution, purification of the Pu by ion exchange, precipitation, and conversion to oxide by calcination.

Lumetta, Gregg J.; Meier, David E.; Tingey, Joel M.; Casella, Amanda J.; Delegard, Calvin H.; Edwards, Matthew K.; Jones, Susan A.; Rapko, Brian M.

2014-08-05

47

Comparison of Spectroscopic Data with Cluster Calculations of Plutonium, Plutonium Dioxide and Uranium Dioxide  

SciTech Connect

Using spectroscopic data produced in the experimental investigations of bulk systems, including X-Ray Absorption Spectroscopy (XAS), Photoelectron Spectroscopy (PES) and Bremstrahlung Isochromat Spectroscopy (BIS), the theoretical results within for UO{sub 2}{sup 6}, PuO{sub 2}{sup 6} and Pu{sup 7} clusters have been evaluated. The calculations of the electronic structure of the clusters have been performed within the framework of the Relativistic Discrete-Variational Method (RDV). The comparisons between the LLNL experimental data and the Russian calculations are quite favorable. The cluster calculations may represent a new and useful avenue to address unresolved questions within the field of actinide electron structure, particularly that of Pu. Observation of the changes in the Pu electronic structure as a function of size suggests interesting implications for bulk Pu electronic structure.

Tobin, J G; Yu, S W; Chung, B W; Ryzhkov, M V; Mirmelstein, A

2012-05-15

48

31. VIEW OF A WORKER HOLDING A PLUTONIUM 'BUTTON.' PLUTONIUM, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. VIEW OF A WORKER HOLDING A PLUTONIUM 'BUTTON.' PLUTONIUM, A MAN-MADE SUBSTANCE, WAS RARE. SCRAPS RESULTING FROM PRODUCTION AND PLUTONIUM RECOVERED FROM RETIRED NUCLEAR WEAPONS WERE REPROCESSED INTO VALUABLE PURE-PLUTONIUM METAL (9/19/73). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

49

Plutonium radiation surrogate  

DOEpatents

A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

Frank, Michael I. (Dublin, CA)

2010-02-02

50

Nitrogen Dioxide  

MedlinePLUS

... here: EPA Home Air & Radiation Six Common Pollutants Nitrogen Dioxide Announcements October 5, 2012 - EPA proposes revisions to NO 2 monitoring requirements Learn More Nitrogen dioxide (NO 2 ) is one of a group ...

51

Plutonium dissolution process  

DOEpatents

A two-step process for dissolving plutonium metal, which two steps can be carried out sequentially or simultaneously. Plutonium metal is exposed to a first mixture containing approximately 1.0M-1.67M sulfamic acid and 0.0025M-0.1M fluoride, the mixture having been heated to a temperature between 45.degree. C. and 70.degree. C. The mixture will dissolve a first portion of the plutonium metal but leave a portion of the plutonium in an oxide residue. Then, a mineral acid and additional fluoride are added to dissolve the residue. Alteratively, nitric acid in a concentration between approximately 0.05M and 0.067M is added to the first mixture to dissolve the residue as it is produced. Hydrogen released during the dissolution process is diluted with nitrogen.

Vest, Michael A. (Oak Park, IL); Fink, Samuel D. (Aiken, SC); Karraker, David G. (Aiken, SC); Moore, Edwin N. (Aiken, SC); Holcomb, H. Perry (North Augusta, SC)

1996-01-01

52

Disposition of separated plutonium  

Microsoft Academic Search

In the immediate term, plutonium, recovered from dismantled nuclear warheads and from civil reprocessing plants, will have to be stored securely, and under international safeguards if possible. In the intermediate term, the principal alternatives for disposition of this plutonium are: irradiation in mixed?oxide (MOX) fuel assemblies in commercial unmodified light?water reactors or in specially adapted light?water reactors capable of operating

Frans Berkhout; Anatoli Diakov; Harold Feiveson; Helen Hunt; Edwin Lyman; Marvin Miller; Frank von Hippel

1993-01-01

53

Surface blistering and flaking of sintered uranium dioxide samples under high dose gas implantation and annealing  

E-print Network

to the pressurization of the fuel rod. Regarding the fuel integrity, a first conservative assumption is to consider of Ronchi et al. [1] reports that a plutonium dioxide sample reduced into powder during normal handling

Boyer, Edmond

54

INTERCOMPARISON OF PLUTONIUM-239 MEASUREMENTS  

EPA Science Inventory

In 1977 the U.S. Environmental Protection Agency distributed calibrated solutions of plutonium-239 to laboratories interested in participating in an intercomparison study of plutonium analysis. Participants were asked to perform a quantitative radioactivity analysis of the soluti...

55

Lithium metal reduction of plutonium oxide to produce plutonium metal  

DOEpatents

A method is described for the chemical reduction of plutonium oxides to plutonium metal by the use of pure lithium metal. Lithium metal is used to reduce plutonium oxide to alpha plutonium metal (alpha-Pu). The lithium oxide by-product is reclaimed by sublimation and converted to the chloride salt, and after electrolysis, is removed as lithium metal. Zinc may be used as a solvent metal to improve thermodynamics of the reduction reaction at lower temperatures. Lithium metal reduction enables plutonium oxide reduction without the production of huge quantities of CaO--CaCl.sub.2 residues normally produced in conventional direct oxide reduction processes.

Coops, Melvin S. (Livermore, CA)

1992-01-01

56

Radiolytic effects of plutonium.  

SciTech Connect

Plutonium isotopes, most of them a-emitters, cause radiolytic changes in the matrix, in whic h they are embedded. The internal irradiation of Pu metal or its alloys results in physical changes, largel y as a result of the formation of helium bubbles, well-known to material scientists and weapons specialists . In all other media where plutonium occurs, usually as Pu'+ in an ionic form, the results of irradiation ar e chemical in nature. Homogenous media containing Pu, are often aqueous or non-aqueous solutions o f plutonium compounds, mostly originating during processing of spent nuclear fuel or from Pu processing . Heterogenous matrices containing plutonium are more complex from the point of view of radiolysis; they usually contain a variety of combinations of common materials contaminated with radionuclides . This class of radioactive materials represents a challenge for the management of plutonium waste . One has to consider a range of time scales for radiolytic effects (and consequently a several orders o f magnitude range of the cumulative dose) beginning with waste generation, through packaging, transportation, to the period of final storage . Final storage could be for thousands of years in deep geologic repositories . At every ' stage of that time scale, radiolysis proceeds continuously an d cumulative effects c an complicate operating procedures and final disposition . The results presented here have been obtained from experiments that have irradiated of model materials, which are typically the objects of contamination with plutonium . They were irradiated with linearly accelerated electrons up to very high dose rates, adjusted to simulate any contamination at any point on the time scale .

Zagorski, Z. (Zbigniew); Dziewinski, J. J. (Jacek J.); Conca, James L.

2003-01-01

57

Plutonium 239 Equivalency Calculations  

SciTech Connect

This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.

Wen, J

2011-05-31

58

Plutonium microstructures. Part 1  

SciTech Connect

This report is the first of three parts in which Los Alamos and Lawrence Livermore National Laboratory metallographers exhibit a consolidated set of illustrations of inclusions that are seen in plutonium metal as a consequence of inherent and tramp impurities, alloy additions, and thermal or mechanical treatments. This part includes illustrations of nonmetallic and intermetallic inclusions characteristic of major impurity elements as an aid to identifying unknowns. It also describes historical aspects of the increased purity of laboratory plutonium samples, and it gives the composition of the etchant solutions and describes the etching procedure used in the preparation of each illustrated sample. 25 figures.

Cramer, E.M.; Bergin, J.B.

1981-09-01

59

Plutonium in Concentrated Solutions  

SciTech Connect

Complex, high ionic strength media are used throughout the plutonium cycle, from its processing and purification in nitric acid, to waste storage and processing in alkaline solutions of concentrated electrolytes, to geologic disposal in brines. Plutonium oxidation/reduction, stability, radiolysis, solution and solid phase chemistry have been studied in such systems. In some cases, predictive models for describing Pu chemistry under such non-ideal conditions have been developed, which are usually based on empirical databases describing specific ion interactions. In Chapter 11, Non-Ideal Systems, studies on the behavior of Pu in various complex media and available model descriptions are reviewed.

Clark, Sue B.; Delegard, Calvin H.

2002-08-01

60

METHOD FOR OBTAINING PLUTONIUM METAL AND ALLOYS OF PLUTONIUM FROM PLUTONIUM TRICHLORIDE  

Microsoft Academic Search

A process is given for both reducing plutonium trichloride to plutonium ; metal using cerium as the reductant and simultaneously alloying such plutonium ; metal with an excess of cerium or cerium and cobalt sufficient to yield the ; desired nuclear reactor fuel composition. The process is conducted at a ; temperature from about 550 to 775 deg C, at

J. G. Reavis; J. A. Leary; W. J. Maraman

1962-01-01

61

PRESSURE DEVELOPMENT IN SEALED CONTAINERS WITH PLUTONIUM BEARING MATERIALS  

SciTech Connect

Gas generation by plutonium-bearing materials in sealed containers has been studied. The gas composition and pressure are determined over periods from months to years. The Pu-bearing materials studied represent those produced by all of the major processes used by DOE in the processing of plutonium and include the maximum amount of water (0.5% by weight) allowed by DOE's 3013 Standard. Hydrogen generation is of high interest and the Pu-bearing materials can be classed according to how much hydrogen is generated. Hydrogen generation by high-purity plutonium oxides packaged under conditions typical for actual 3013 materials is minimal, with very low generation rates and low equilibrium pressures. Materials with chloride salt impurities have much higher hydrogen gas generation rates and result in the highest observed equilibrium hydrogen pressures. Other materials such as those with high metal oxide impurities generate hydrogen at rates in between these extremes. The fraction of water that is converted to hydrogen gas as equilibrium is approached ranges from 0% to 25% under conditions typical of materials packaged to the 3013 Standard. Generation of both hydrogen and oxygen occurs when liquid water is present. The material and moisture conditions that result in hydrogen and oxygen generation for high-purity plutonium oxide and chloride salt-bearing plutonium oxide materials have been characterized. Other gases that are observed include nitrous oxide, carbon dioxide, carbon monoxide, and methane.

Duffey, J.; Livingston, R.

2010-02-01

62

Plutonium: An introduction  

SciTech Connect

This report is a summary of the history and properties of plutonium. It presents information on the atoms, comparing chemical and nuclear properties. It looks at the history of the atom, including its discovery and production methods. It summarizes the metallurgy and chemistry of the element. It also describes means of detecting and measuring the presence and quantity of the element.

Condit, R.H.

1993-10-01

63

Atomic spectrum of plutonium  

SciTech Connect

This report contains plutonium wavelengths, energy level classifications, and other spectroscopic data accumulated over the past twenty years at Laboratoire Aime Cotton (LAC) Argonne National Laboratory (ANL), and Lawrence Livermore National Laboratory (LLNL). The primary purpose was term analysis: deriving the energy levels in terms of quantum numbers and electron configurations, and evaluating the Slater-Condon and other parameters from the levels.

Blaise, J.; Fred, M.; Gutmacher, R.G.

1984-08-01

64

Materials identification and surveillance project item evaluation: Items, impure plutonium oxide (ATL27960) and pure plutonium oxide (PEOR3258)  

SciTech Connect

In this report, Los Alamos scientists characterize properties relevant to storage of an impure plutonium oxide (74 mass % plutonium) in accordance with the Department of Energy (DOE) standard DOE-STD-3013-96. This oxide is of interest because it is the first impure plutonium oxide sample to be evaluated and it is similar to other materials that must be stored. Methods used to characterize the oxide at certain points during calcination include surface-area analyses, mass loss-on-ignition (LOI) measurements, elemental analysis, moisture-adsorption measurements, and quantitative supercritical-CO{sub 2} extraction of adsorbed water. Significant decreases in the LOI and surface area occurred as the oxide was calcined at progressively increasing temperatures. Studies indicate that supercritical-CO{sub 2} extraction is an effective method for removing adsorbed water from oxides. We extracted the water from powdered oxides (high-purity ZrO{sub 2}, pure PuO{sub 2}, and impure plutonium oxide) using CO{sub 2} at 3000 psi pressure and 75{degrees}C, and we quantitatively determined it by using gravimetric and dew-point procedures. The effectiveness of the extraction method is demonstrated by good agreement between the amounts of water extracted from pure zirconium and plutonium dioxides and the mass changes obtained from LOI analyses. However, the amount of moisture (0.025 mass %) extracted from the impure plutonium oxide after it had been calcined at 950{degrees}C and stored for a period of months is much less than the LOI value (0.97 mass %). These results imply that the impure plutonium oxide is free of adsorbed water after calcination at 950{degrees}C, even though the sample does not satisfy the LOI requirement of <0.50 mass % for storage.

Allen, T.; Appert, Q.; Davis, C. [and others

1997-03-01

65

Plutonium Finishing Plant. Interim plutonium stabilization engineering study  

SciTech Connect

This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage.

Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J. [Pacific Northwest Lab., Richland, WA (United States); Nass, R. [Nuclear Fuel Services, Inc. (United States)

1995-08-01

66

Plutonium age dating reloaded  

NASA Astrophysics Data System (ADS)

Although the age determination of plutonium is and has been a pillar of nuclear forensic investigations for many years, additional research in the field of plutonium age dating is still needed and leads to new insights as the present work shows: Plutonium is commonly dated with the help of the 241Pu/241Am chronometer using gamma spectrometry; in fewer cases the 240Pu/236U chronometer has been used. The age dating results of the 239Pu/235U chronometer and the 238Pu/234U chronometer are scarcely applied in addition to the 240Pu/236U chronometer, although their results can be obtained simultaneously from the same mass spectrometric experiments as the age dating result of latter. The reliability of the result can be tested when the results of different chronometers are compared. The 242Pu/238U chronometer is normally not evaluated at all due to its sensitivity to contamination with natural uranium. This apparent 'weakness' that renders the age dating results of the 242Pu/238U chronometer almost useless for nuclear forensic investigations, however turns out to be an advantage looked at from another perspective: the 242Pu/238U chronometer can be utilized as an indicator for uranium contamination of plutonium samples and even help to identify the nature of this contamination. To illustrate this the age dating results of all four Pu/U clocks mentioned above are discussed for one plutonium sample (NBS 946) that shows no signs of uranium contamination and for three additional plutonium samples. In case the 242Pu/238U chronometer results in an older 'age' than the other Pu/U chronometers, contamination with either a small amount of enriched or with natural or depleted uranium is for example possible. If the age dating result of the 239Pu/235U chronometer is also influenced the nature of the contamination can be identified; enriched uranium is in this latter case a likely cause for the missmatch of the age dating results of the Pu/U chronometers.

Sturm, Monika; Richter, Stephan; Aregbe, Yetunde; Wellum, Roger; Mayer, Klaus; Prohaska, Thomas

2014-05-01

67

4. VIEW OF PLUTONIUM CANISTER ON CHAINVEYOR. SCRAP PLUTONIUM WAS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VIEW OF PLUTONIUM CANISTER ON CHAINVEYOR. SCRAP PLUTONIUM WAS COLLECTED INTO CANS AT INDIVIDUAL WORKSTATIONS. THE CANS WERE TRANSFERRED VIA THE CHAIN CONVEYOR TO A WORKSTATION IN MODULE C WHERE THE MATERIAL WAS COMPRESSED INTO BRIQUETTES FOR LATER USE. (6/20/93) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

68

Plutonium Air Shipments  

NSDL National Science Digital Library

The Nuclear Control Institute created a web site in response to a proposed standard for the shipment of radioactive materials. This site presents two world maps showing both sea and air routes that are planned or already in use for the shipment of plutonium. A series of papers by NCI-affiliated scientists and observers on the subject of radioactive materials shipments sets out the NCI position against such shipments.

69

Manufacturing of Plutonium Tensile Specimens  

SciTech Connect

Details workflow conducted to manufacture high density alpha Plutonium tensile specimens to support Los Alamos National Laboratory's science campaigns. Introduces topics including the metallurgical challenge of Plutonium and the use of high performance super-computing to drive design. Addresses the utilization of Abaqus finite element analysis, programmable computer numerical controlled (CNC) machining, as well as glove box ergonomics and safety in order to design a process that will yield high quality Plutonium tensile specimens.

Knapp, Cameron M [Los Alamos National Laboratory

2012-08-01

70

Proliferation aspects of plutonium recycling  

Microsoft Academic Search

Plutonium recycling offers benefits in an energy perspective of sustainable development, and, moreover it contributes to non-proliferation. Prior to recycling, reactor-grade plutonium from light-water reactors does not lend itself easily to the assembly of explosive nuclear devices; thereafter, practically not at all. Control systems for material security and non-proliferation should identify and adopt several categories of plutonium covering various isotopic

Bruno Pellaud

2002-01-01

71

Prolifération et recyclage du plutonium  

NASA Astrophysics Data System (ADS)

Plutonium recycling offers benefits in an energy perspective of sustainable development, and, moreover it contributes to non-proliferation. Prior to recycling, reactor-grade plutonium from light-water reactors does not lend itself easily to the assembly of explosive nuclear devices; thereafter, practically not at all. Control systems for material security and non-proliferation should identify and adopt several categories of plutonium covering various isotopic mixtures associated with different fuel types, in order to better reflect the risks and to better focus their controls. The author proposes the adoption of three categories of plutonium. To cite this article: B. Pellaud, C. R. Physique 3 (2002) 1067-1079.

Pellaud, Bruno

2002-10-01

72

Photochemical preparation of plutonium pentafluoride  

DOEpatents

The novel compound plutonium pentafluoride may be prepared by the photodissociation of gaseous plutonium hexafluoride. It is a white solid of low vapor pressure, which consists predominantly of a face-centered cubic structure with a.sub.o =4.2709.+-.0.0005 .ANG..

Rabideau, Sherman W. (Los Alamos, NM); Campbell, George M. (Los Alamos, NM)

1987-01-01

73

Carbon dioxide  

NSDL National Science Digital Library

Bubbles are an indicator of a chemical reaction. An indicator is an object, material, or organism that tells you if a specific substance is present. In the sugar test, carbon dioxide gas release is an indicator that yeast is using sugar to grow. The more gas produced, the more sugar a specific substance contains.

Arie Melamed-Katz (None; )

2007-06-19

74

LANL Plutonium-Processing Facilities National Security  

E-print Network

TA-55 PF-4 LANL Plutonium-Processing Facilities National Security At the Los Alamos National Laboratory (LANL), virtually all plutonium operations occur within the Plutonium Facility at Tech- nical Area, and it is the only fully operational, full capability plutonium facility in the nation. Thus, TA-55 supports a wide

75

APPENDIX G Partition Coefficients For Plutonium  

E-print Network

APPENDIX G Partition Coefficients For Plutonium #12;Appendix G Partition Coefficients For Plutonium G.1.0 Background A number of studies have focussed on the adsorption behavior of plutonium that Kd values for plutonium typically range over 4 orders of magnitude (Thibault et al., 1990). Also

76

Plutonium oxide dissolution  

SciTech Connect

Several processing options for dissolving plutonium oxide (PuO{sub 2}) from high-fired materials have been studied. The scoping studies performed on these options were focused on PuO{sub 2} typically generated by burning plutonium metal and PuO{sub 2} produced during incineration of alpha contaminated waste. At least two processing options remain applicable for dissolving high-fired PuO{sub 2} in canyon dissolvers. The options involve solid solution formation of PuO{sub 2} With uranium oxide (UO{sub 2}) and alloying incinerator ash with aluminum. An oxidative dissolution process involving nitric acid solutions containing a strong oxidizing agent, such as cerium (IV), was neither proven nor rejected. This uncertainty was due to difficulty in regenerating cerium (IV) ions during dissolution. However, recent work on silver-catalyzed dissolution of PuO{sub 2} with persulfate has demonstrated that persulfate ions regenerate silver (II). Use of persulfate to regenerate cerium (IV) or bismuth (V) ions during dissolution of PuO{sub 2} materials may warrant further study.

Gray, J.H.

1992-09-30

77

Plutonium oxide dissolution  

SciTech Connect

Several processing options for dissolving plutonium oxide (PuO[sub 2]) from high-fired materials have been studied. The scoping studies performed on these options were focused on PuO[sub 2] typically generated by burning plutonium metal and PuO[sub 2] produced during incineration of alpha contaminated waste. At least two processing options remain applicable for dissolving high-fired PuO[sub 2] in canyon dissolvers. The options involve solid solution formation of PuO[sub 2] With uranium oxide (UO[sub 2]) and alloying incinerator ash with aluminum. An oxidative dissolution process involving nitric acid solutions containing a strong oxidizing agent, such as cerium (IV), was neither proven nor rejected. This uncertainty was due to difficulty in regenerating cerium (IV) ions during dissolution. However, recent work on silver-catalyzed dissolution of PuO[sub 2] with persulfate has demonstrated that persulfate ions regenerate silver (II). Use of persulfate to regenerate cerium (IV) or bismuth (V) ions during dissolution of PuO[sub 2] materials may warrant further study.

Gray, J.H.

1992-09-30

78

Probing phonons in plutonium  

SciTech Connect

Plutonium (Pu) is well known to have complex and unique physico-chemical properties. Notably, the pure metal exhibits six solid-state phase transformations with large volume expansions and contractions along the way to the liquid state: {alpha} {yields} {beta} {yields} {gamma} {yields} {delta} {yields} {delta}{prime} {yields} {var_epsilon} {yields} liquid. Unalloyed Pu melts at a relatively low temperature {approx}640 C to yield a higher density liquid than that of the solid from which it melts, (Figure 1). Detailed understanding of the properties of plutonium and plutonium-based alloys is critical for the safe handling, utilization, and long-term storage of these important, but highly toxic materials. However, both technical and and safety issues have made experimental observations extremely difficult. Phonon dispersion curves (PDCs) are key experimenta l data to the understanding of the basic properties of Pu materials such as: force constants, sound velocities, elastic constants, thermodynamics, phase stability, electron-phonon coupling, structural relaxation, etc. However, phonon dispersion curves (PDCs) in plutonium (Pu) and its alloys have defied measurement for the past few decades since the discovery of this element in 1941. This is due to a combination of the high thermal-neutron absorption cross section of plutonium and the inability to grow the large single crystals (with dimensions of a few millimeters) necessary for inelastic neutron scattering. Theoretical simulations of the Pu PDC continue to be hampered by the lack of suitable inter -atomic potentials. Thus, until recently the PDCs for Pu and its alloys have remained unknown experimentally and theoretically. The experimental limitations have recently been overcome by using a tightly focused undulator x-ray micro-beam scattered from single -grain domains in polycrystalline specimens. This experimental approach has been applied successfully to map the complete PDCs of an fcc d-Pu-Ga alloy using the high resolution inelastic x-ray scattering (HRIXS) capability on ID28. The complete PDCs for an fcc Pu-0.6 wt% Ga alloy are plotted in Figure 2, and represent the first full set of phonon dispersions ever determined for any Pu-bearing materials. The solid curves (red) are calculated using a standard Born-von Karman (B-vK) force constant model. An adequate fit to the experimental data is obtained if interactions up to the fourth-nearest neighbours are included. The dashed curves (blue) are recent dynamical mean field theory (DMFT) results by Dai et al. The elastic moduli calculated from the slopes of the experimental phonon dispersion curves near the {Lambda} point are: C{sub 11} = 35.3 {+-} 1.4 GPa, C{sub 12} = 25.5 {+-} 1.5 GPa and C{sub 44} = 30.53 {+-} 1.1 GPa. These values are in excellent agreement with those of the only other measurement on a similar alloy (1 wt % Ga) using ultrasonic techniques as well as with those recently calculated from a combined DMFT and linear response theory for pure {delta}-Pu. Several unusual features, including a large elastic anisotropy, a small shear elastic modulus C{prime}, a Kohn-like anomaly in the T{sub 1}[011] branch, and a pronounced softening of the [111] transverse modes are found. These features can be related to the phase transitions of plutonium and to strong coupling between the lattice structure and the 5f valence instabilities. The HRIXS results also provide a critical test for theoretical treatments of highly correlated 5f electron systems as exemplified by recent dynamical mean field theory (DMFT) calculations for {delta}-plutonium. The experimental-theoretical agreements shown in Figure 2 in terms of a low shear elastic modulus C{prime}, a Kohn-like anomaly in the T{sub 1}[011] branch, and a large softening of the T[111] modes give credence to the DMFT approach for the theoretical treatment of 5f electron systems of which {delta}-Pu is a classic example. However, quantitative differences remain. These are the position of the Kohn anomaly along the T{sub 1}[011] branch, the energy maximum of the T[111] mode s

Wong, Joe; Krisch, M.; Farber, D.; Occelli, F.; Schwartz, A.; Chiang, T.C.; Wall, M.; Boro, C.; Xu, Ruqing (UIUC); (LLNL); (ESRF); (LANL)

2010-11-16

79

Low temperature oxidation of plutonium  

SciTech Connect

The initial oxidation of gallium stabilized {delta}-plutonium metal at 193 K has been followed using x-ray photoelectron spectroscopy. On exposure to Langmuir quantities of oxygen, plutonium rapidly forms a trivalent oxide followed by a tetravalent plutonium oxide. The growth modes of both oxides have been determined. Warming the sample in vacuum, the tetravalent oxide reduces to the trivalent oxide. The kinetics of this reduction reaction have followed and the activation energy has been determined to be 38.8 kJ mol{sup -1}.

Nelson, Art J. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Roussel, Paul [AWE, Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

2013-05-15

80

Raman spectroscopy of plutonium dioxide and related materials  

NASA Astrophysics Data System (ADS)

Evidence to support the Raman assignments of the 1LO (578 cm-1) and 2LO (1158 cm-1) lattice vibrations for PuO2 material is presented. The T2g signal is established at 476 ± 2 cm-1 in agreement with literature values. An increase of the 1LO band and an increase of the unit cell lattice parameter with ageing in our samples are found not to be a consequence of PuO2+x formation but rather a result of simple lattice defects due to radiation damage. The Raman spectrum of AnO2(OH)2?xH2O (An = Np, Pu) and laser induced decomposition products suggest that the transition to AnO2 involves Np2O5 for neptunium but no such analogue could be detected for Pu. The presence of a band around 1150 ± 10 cm-1 for a range of MO2 fluorite structures (CeO2, ThO2, UO2, NpO2 and PuO2) suggests that this band is not derived from crystal field electronic f-f transitions as proposed previously and supports recent suggestions that it is the first overtone of the 1LO lattice vibration. The spectrum of PuO2 is taken across a wide wavenumber range (200-4000 cm-1) and additional signals (2116 and 2611 cm-1) not previously reported have been observed but are not yet assigned with confidence.

Sarsfield, Mark J.; Taylor, Robin J.; Puxley, Christopher; Steele, Helen M.

2012-08-01

81

Deflagration in stainless steel storage containers containing plutonium dioxide  

SciTech Connect

Detonation of hydrogen and oxygen in stainless steel storage containers produces maximum pressures of 68.5 psia and 426.7 psia. The cylinders contain 3,000 g of PuO{sub 2} with 0.05 wt% and 0.5 wt% water respectively. The hydrogen and oxygen are produced by the alpha decomposition of the water. Work was performed for the Savannah River Site.

Kleinschmidt, P.D.

1996-02-01

82

FORM AND AGING OF PLUTONIUM IN SAVANNAH RIVER SITE WASTE TANK 18  

SciTech Connect

This report provides a summary of the effects of aging on and the expected forms of plutonium in Tank 18 waste residues. The findings are based on available information on the operational history of Tank 18, reported analytical results for samples taken from Tank 18, and the available scientific literature for plutonium under alkaline conditions. These findings should apply in general to residues in other waste tanks. However, the operational history of other waste tanks should be evaluated for specific conditions and unique operations (e.g., acid cleaning with oxalic acid) that could alter the form of plutonium in heel residues. Based on the operational history of other tanks, characterization of samples from the heel residues in those tanks would be appropriate to confirm the form of plutonium. During the operational period and continuing with the residual heel removal periods, Pu(IV) is the dominant oxidation state of the plutonium. Small fractions of Pu(V) and Pu(VI) could be present as the result of the presence of water and the result of reactions with oxygen in air and products from the radiolysis of water. However, the presence of Pu(V) would be transitory as it is not stable at the dilute alkaline conditions that currently exists in Tank 18. Most of the plutonium that enters Savannah River Site (SRS) high-level waste (HLW) tanks is freshly precipitated as amorphous plutonium hydroxide, Pu(OH){sub 4(am)} or hydrous plutonium oxide, PuO{sub 2(am,hyd)} and coprecipitated within a mixture of hydrous metal oxide phases containing metals such as iron, aluminum, manganese and uranium. The coprecipitated plutonium would include Pu{sup 4+} that has been substituted for other metal ions in crystal lattice sites, Pu{sup 4+} occluded within hydrous metal oxide particles and Pu{sup 4+} adsorbed onto the surface of hydrous metal oxide particles. The adsorbed plutonium could include both inner sphere coordination and outer sphere coordination of the plutonium. PuO{sub 2(am,hyd)} is also likely to be present in deposits and scales that have formed on the steel surfaces of the tank. Over the operational period and after closure of Tank 18, Ostwald ripening has and will continue to transform PuO{sub 2(am,hyd)} to a more crystalline form of plutonium dioxide, PuO{sub 2(c)}. After bulk waste removal and heel retrieval operations, the free hydroxide concentration decreased and the carbonate concentration in the free liquid and solids increased. Consequently, a portion of the PuO{sub 2(am,hyd)} has likely been converted to a hydroxy-carbonate complex such as Pu(OH){sub 2}(CO{sub 3}){sub (s)}. or PuO(CO{sub 3}) {center_dot} xH{sub 2}O{sub (am)}. Like PuO{sub 2(am,hyd)}, Ostwald ripening of Pu(OH){sub 2}(CO{sub 3}){sub (s)} or PuO(CO{sub 3}) {center_dot} xH{sub 2}O{sub (am)} would be expected to occur to produce a more crystalline form of the plutonium carbonate complex. Due to the high alkalinity and low carbonate concentration in the grout formulation, it is expected that upon interaction with the grout, the plutonium carbonate complexes will transform back into plutonium hydroxide. Although crystalline plutonium dioxide is the more stable thermodynamic state of Pu(IV), the low temperature and high water content of the waste during the operating and heel removal periods in Tank 18 have limited the transformation of the plutonium into crystalline plutonium dioxide. During the tank closure period of thousands of years, transformation of the plutonium into a more crystalline plutonium dioxide form would be expected. However, the continuing presence of water, reaction with water radiolysis products, and low temperatures will limit the transformation, and will likely maintain an amorphous Pu(OH){sub 4} or PuO{sub 2(am,hyd)} form on the surface of any crystalline plutonium dioxide produced after tank closure. X-ray Absorption Spectroscopic (XAS) measurements of Tank 18 residues are recommended to confirm coordination environments of the plutonium. If the presence of PuO(CO{sub 3}){sub (am,hyd)} is confirmed by XAS, it is recommended that e

Hobbs, D.

2012-02-24

83

Quarterly progress report, April 2-June 29, 1979 - Study of plutonium oxide leak rates from shipping containers.  

SciTech Connect

The study was initiated in October 1976. Several tasks are to be undertaken in this study which, when combined, have the end objective of defining the leak rates of plutonium dioxide powder from characterized leaks. Each task is identified and the progress during the reporting period is briefly described.

Not Available

1979-07-01

84

Plutonium solution analyzer  

SciTech Connect

A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%-O.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40-240 g/L and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4-4.0 g/L. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 mL of each sample and standard, and generates waste at the rate of about 1.5 mL per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded).

Burns, D.A.

1994-09-01

85

Plutonium focus area  

SciTech Connect

To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure.

NONE

1996-08-01

86

Plutonium shipments - a supplement  

SciTech Connect

By means of a supplement to the stimulating analysis found in the comprehensive article by Professor Jon Van Dyke on `Sea Shipment of Japanese Plutonium under International Law`, published in Volume 24 of this journal, we feel that the following clarifications and additions are appropriate. Radioactive wastes are not covered by the 1989 Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and Their Disposal. Fir this reason, the Basel Conference adopted on March 22, 1989, along with the convention, Resolution 5 on Harmonization of Procedures of the Basel Convention and the Code of Practice for International Transactions Involving Nuclear Wastes. In accordance with Resolution 5, the provisions of the Basel Convention were taken into full account during the elaboration of the IAEA code, which ultimately was adopted by Resolution GC(XXXIV)/530 of the General Conference on Code of Practice on the International Transboundary Movement of Radioactive Waste (TMRW) of September 21, 1990. The IAEA code of practice and the respective regional instruments affirm, with respect to TMRW, the general principles of the Basel Convention, including the critical regime of prior notification and prior informed consent (PIC) that extend the scope of duties of notification, environmental impact assessment, and consultation with respect to transboundary interference as the duties have evolved under existing customary law.

Kwiatkowska, B.; Soons, A. [Netherlands Institute for the Law of the Sea, Utrecht (Netherlands)

1994-10-01

87

Control of civilian plutonium inventories using burning in a non-fertile fuel  

NASA Astrophysics Data System (ADS)

The increasing inventories of plutonium generated by commercial nuclear power production represent a potential source for proliferation of nuclear weapons. To address this threat we propose separating the plutonium from the other constituents of commercial reactor spent fuel and burning it in a non-fertile fuel based on a zirconium dioxide matrix. The separation can be performed by the Purex process currently in use, but we recommend development of a more compact separation technology that would produce less secondary waste than currently used technology and would allow for more stringent accounting of plutonium inventories. The non-fertile fuel is designed for use in conventional light water power reactors and does not require development of new reactor technology.

Oversby, V. M.; McPheeters, C. C.; Degueldre, C.; Paratte, J. M.

1997-05-01

88

The vaporisation behaviour of americium dioxide by use of mass spectrometry  

NASA Astrophysics Data System (ADS)

The vaporisation behaviour of americium dioxide in vacuum at high temperatures up to 2400 K has been studied. A Knudsen cell coupled with a mass spectrometer was used to perform vapour pressure measurements. The ionisation efficiency curves of Am +, AmO + and AmO2+ were simultaneously recorded. Appearance potentials of the key molecular species were determined by varying the energy of the ionising electrons at constant temperature. The partial and total vapour pressures above the americium oxide samples measured as a function of the temperature. The results on the vapour pressure of the pure americium dioxide samples were discussed together with the available literature data on plutonium dioxide containing small amounts of americium. Additional measurements have been performed on a mixed dioxide sample of plutonium containing 6.1 wt.% americium.

Gotcu-Freis, P.; Colle, J.-Y.; Hiernaut, J.-P.; Konings, R. J. M.

2011-02-01

89

Plutonium adsorption by selected inorganic compounds  

Microsoft Academic Search

Plutonium may be removed from aqueous solution by adsorption on inorganic materials. Hydroxylapatite, dibasic and tribasic calcium phosphate, calcium cyanamide, and sodium titanate are particularly noteworthy for their ability to concentrate plutonium. The extent of adsorption and pH of maximum adsorption depend upon the chemical form of the dissolved plutonium.

1980-01-01

90

Plutonium adsorption by selected inorganic compounds  

SciTech Connect

Plutonium may be removed from aqueous solution by adsorption on inorganic materials. Hydroxylapatite, dibasic and tribasic calcium phosphate, calcium cyanamide, and sodium titanate are particularly noteworthy for their ability to concentrate plutonium. The extent of adsorption and pH of maximum adsorption depend upon the chemical form of the dissolved plutonium.

Silver, G.L.

1980-10-10

91

Plutonium recycle in French PWR plants  

Microsoft Academic Search

A significant amount of plutonium from pressurized water reactor (PWR) spent fuel reprocessing will be available in France as soon as 1990. Due to the breeder program delay, this amount will be sufficient to permit plutonium recycle in a large number of French PWR plants. According to the French spent fuel reprocessing policy, plutonium recycling approaches two concerns: (1) economic

M. Rome; G. Francillon; M. le Bars

1987-01-01

92

Plutonium-the element of surprise  

E-print Network

Plutonium-the element of surprise G.R.ChoppinandB.E.Stout This year marked the soth annivrsary ol the original isolation o{ plutonium, making ita relativenewcomerto the PeriodicTable.Ovrthe past 50 years plutonium has become more familiar to tho generslpublic than manyothor,olderelem6nts

Short, Daniel

93

Preparation of Uranium and Plutonium Metals  

Microsoft Academic Search

A new process for preparing uranium and plutonium metals has been developed. The process is based on the high extractability of the elements with sodium amalgam from aqueous solutions. After extracting the uranium or plutonium with sodium amalgam, the resulting amalgam was heated in vacuum so that mercury and sodium were separated to produce uranium or plutonium metal. The mercury

Yoshii KOBAYASHI; Akira SAITO

1975-01-01

94

Plutonium removal limit for the disposition of plutonium-bearing materials  

SciTech Connect

Recent changes in world politics have resulted in the United States reducing its nuclear weapons and stopping plutonium production. Prior plutonium production, dismantling warheads, and decontamination and decommissioning some facilities have produced plutonium-bearing materials which must continue to be managed. As each lot of material is processed, the processor must decide whether to remove the plutonium before discarding the material or to discard it without plutonium removal. DOE has developed a new method of making this decision, called the Plutonium Removal Limit System (PRLS). The system is based on defining a plutonium concentration above which the cost of disposing of plutonium-bearing materials will be less if plutonium is recovered and below which the cost will be less if plutonium is discarded (following suitable waste treatment). This method minimizes the overall cost to DOE for disposing of the existing inventory of plutonium-bearing materials. The method was used to analyze the plutonium-discard limit for all categories of plutonium-bearing materials currently at each site. This analysis indicated the need to standardize the way sites make the remove-versus-discard decision. For this purpose, a set of departmental plutonium removal limits was developed. DOE expects to approve implementing this new method at all facilities handling plutonium-bearing material in FY 93.

White, W.C. [USDOE, Washington, DC (United States); Mowery, B. [Los Alamos National Lab., NM (United States); Felt, R. [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States); King, F.; Hurley, J.D. [Westinghouse Savannah River Co., Aiken, SC (United States)

1992-12-31

95

Plutonium removal limit for the disposition of plutonium-bearing materials  

SciTech Connect

Recent changes in world politics have resulted in the United States reducing its nuclear weapons and stopping plutonium production. Prior plutonium production, dismantling warheads, and decontamination and decommissioning some facilities have produced plutonium-bearing materials which must continue to be managed. As each lot of material is processed, the processor must decide whether to remove the plutonium before discarding the material or to discard it without plutonium removal. DOE has developed a new method of making this decision, called the Plutonium Removal Limit System (PRLS). The system is based on defining a plutonium concentration above which the cost of disposing of plutonium-bearing materials will be less if plutonium is recovered and below which the cost will be less if plutonium is discarded (following suitable waste treatment). This method minimizes the overall cost to DOE for disposing of the existing inventory of plutonium-bearing materials. The method was used to analyze the plutonium-discard limit for all categories of plutonium-bearing materials currently at each site. This analysis indicated the need to standardize the way sites make the remove-versus-discard decision. For this purpose, a set of departmental plutonium removal limits was developed. DOE expects to approve implementing this new method at all facilities handling plutonium-bearing material in FY 93.

White, W.C. (USDOE, Washington, DC (United States)); Mowery, B. (Los Alamos National Lab., NM (United States)); Felt, R. (Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States)); King, F.; Hurley, J.D. (Westinghouse Savannah River Co., Aiken, SC (United States))

1992-01-01

96

Plutonium inventory characterization technical evaluation report  

SciTech Connect

This is a technical report on the data, gathered to date, under WHC- SD-CP-TP-086, Rev. 1, on the integrity of the food pack cans currently being used to store plutonium or plutonium compounds at the Plutonium Finishing Plant. Workplan PFP-96-VO-009, `Inspection of Special Nuclear Material Using X-ray`, was used to gather data on material and containment conditions using real time radiography. Some of those images are included herein. A matrix found in the `Plutonium Inventory Characterization Implementation Plan` was used to categorize different plutonium items based upon the type of material being stored and the life expectancy of the containers.

Wittman, G.R., Westinghouse Hanford

1996-07-10

97

Method of separating thorium from plutonium  

DOEpatents

A method is described for chemically separating plutonium from thorium. Plutonium and thorium to be separated are dissolved in an aqueous feed solution, preferably as the nitrate salts. The feed solution is acidified and sodium nitrite is added to the solution to adjust the valence of the plutonium to the +4 state. A chloride salt, preferably sodium chloride, is then added to the solution to induce formation of an anionic plutonium chloride complex. The anionic plutonium chloride complex and the thorium in solution are then separated by ion exchange on a strong base anion exchange column.

Clifton, D.G.; Blum, T.W.

1984-07-10

98

Method of separating thorium from plutonium  

DOEpatents

A method of chemically separating plutonium from thorium. Plutonium and thorium to be separated are dissolved in an aqueous feed solution, preferably as the nitrate salts. The feed solution is acidified and sodium nitrite is added to the solution to adjust the valence of the plutonium to the +4 state. A chloride salt, preferably sodium chloride, is then added to the solution to induce formation of an anionic plutonium chloride complex. The anionic plutonium chloride complex and the thorium in solution are then separated by ion exchange on a strong base anion exchange column.

Clifton, David G. (Los Alamos, NM); Blum, Thomas W. (Los Alamos, NM)

1984-01-01

99

Plutonium immobilization form evaluation  

SciTech Connect

The 1994 National Academy of Sciences study and the 1997 assessment by DOE`s Office of Nonproliferation and National Security have emphasized the importance of the overall objectives of the Plutonium Disposition Program of beginning disposition rapidly. President Clinton and other leaders of the G-7 plus one (`Political Eight`) group of states, at the Moscow Nuclear Safety And Security Summit in April 1996, agreed on the objectives of accomplishing disposition of excess fissile material as soon as practicable. To meet these objectives, DOE has laid out an aggressive schedule in which large-scale immobilization operations would begin in 2005. Lawrence Livermore National Laboratory (LLNL), the lead laboratory for the development of Pu immobilization technologies for the Department of Energy`s Office of Fissile Materials Disposition (MD), was requested by MD to recommend the preferred immobilization form and technology for the disposition of excess weapons-usable Pu. In a series of three separate evaluations, the technologies for the candidate glass and ceramic forms were compared against criteria and metrics that reflect programmatic and technical objectives: (1) Evaluation of the R&D and engineering data for the two forms against the decision criteria/metrics by a technical evaluation panel comprising experts from within the immobilization program. (2) Integrated assessment by LLNL immobilization management of the candidate technologies with respect to the weighted criteria and other programmatic objectives, leading to a recommendation to DOE/MD on the preferred technology based on technical factors. (3) Assessment of the decision process, evaluation, and recommendation by a peer review panel of independent experts. Criteria used to assess the relative merits of the immobilization technologies were a subset of the criteria previously used by MD to choose among disposition options leading to the Programmatic Environmental Impact Statement and Record of Decision for the Storage and Disposition of Weapons-Usable Fissile Materials, January 1997. Criteria were: (1) resistance to Pu theft, diversion, and recovery by a terrorist organization or rogue nation; (2) resistance to recovery and reuse by host nation; (3) technical viability, including technical maturity, development risk, and acceptability for repository disposal; (4) environmental, safety, and health factors; (5) cost effectiveness; and (6) timeliness. On the basis of the technical evaluation and assessments, in September, 1997, LLNL recommended to DOE/MD that ceramic technologies be developed for deployment in the planned Pu immobilization plant.

Gray, L. W., LLNL

1998-02-13

100

Nature of Nano-Sized Plutonium Particles in Soils at the Hanford Site  

SciTech Connect

The occurrence of plutonium dioxide (PuO2) either from direct deposition or from the precipitation of plutonium-bearing solutions in contaminated soils and sediments has been well described, particularly for the Hanford site in Washington State. However, past research has suggested that plutonium may exist in environmental samples at the Hanford site in chemical forms in addition to large size PuO2 particles and that these previously unidentified nano-sized particles maybe more reactive and thus more likely to influence the environmental mobility of Pu. Here we present evidence for the formation of nano-sized plutonium iron phosphate hydroxide structurally related to the rhabdophane group nanoparticles in 216-Z9 crib sediments from Hanford using transmission electron microscopy (TEM). The distribution and nature of these nanoparticles varied depending on the adjacent phases present. Fine electron probes were used to obtain electron diffraction and electron energy-loss spectra from specific phase regions of the 216-Z9 cribs specimens from fine-grained plutonium oxide and phosphate phases. Energy-loss spectra were used to evaluate the plutonium N4,5 (4d ? 5f ) and iron L2,3 absorption edges. The iron plutonium phosphate formation may depend on the local micro-environment in the sediments, availability of phosphate, and hence the distribution of these minerals may control long-term migration of Pu in the soil. This study also points to the utility of using electron beam methods for determining the identity of actinide phases and their association with other sediment phases.

Buck, Edgar C.; Moore, Dean A.; Czerwinski, Kenneth R.; Conradson, Steven D.; Batuk, Olga; Felmy, Andrew R.

2014-08-06

101

PLUTONIUM FUEL-CASTING FACILITY  

Microsoft Academic Search

An induction-heated glove-box-enclosed casting facility was used at ; Hanford for the melting and casting of experimental plutonium-containing fuel ; alloys. The alloys are prepared in furnaces with removable clay-graphite ; crucibles, supported by rammed alumina containment shells. The furnaces, which ; have capacities of 25 and 50 pounds of aluminum, are tilted by rotary hydraulic ; actuators. Furnace power

L. G. Merker; C. H. Bloomster

1963-01-01

102

Plutonium from Chernobyl in Poland  

Microsoft Academic Search

Samples of coniferous forest litter collected in POland, of known ?-emitters activity, have been analysed for ? emitting plutonium isotopes. Specific as well as surface activities of the samples have been determined. Chernobyl and global fallout components have been distinguished for each sample. The observed maximum surface activity for Chernobyl fallout is above 25 Bq m?2 (for all ?-emitting Pu

Jerzy W. Mietelski

1995-01-01

103

Plutonium Recycle: The Fateful Step  

ERIC Educational Resources Information Center

Calls attention to the fact that if the Atomic Energy Commission proceeds with its plans to authorize the nuclear power industry to use plutonium as a fuel in commercial nuclear reactors around the country, this will result in a dramatic escalation in the risks posed by nuclear power. (PEB)

Speth, J. Gustave; And Others

1974-01-01

104

Plutonium waste incineration using pyrohydrolysis  

SciTech Connect

Waste generated by Savannah River Site (SRS) plutonium operations includes a contaminated organic waste stream. A conventional method for disposing of the organic waste stream and recovering the nuclear material is by incineration. When the organic material is burned, the plutonium remains in the incinerator ash. Plutonium recovery from incinerator ash is highly dependent on the maximum temperature to which the oxide is exposed. Recovery via acid leaching is reduced for a high fired ash (>800{degree}C), while plutonium oxides fired at lower decomposition temperatures (400--800{degrees}C) are more soluble at any given acid concentration. To determine the feasibility of using a lower temperature process, tests were conducted using an electrically heated, controlled-air incinerator. Nine nonradioactive, solid, waste materials were batch-fed and processed in a top-heated cylindrical furnace. Waste material processing was completed using a 19-liter batch over a nominal 8-hour cycle. A processing cycle consisted of 1 hour for heating, 4 hours for reacting, and 3 hours for chamber cooling. The water gas shift reaction was used to hydrolyze waste materials in an atmosphere of 336% steam and 4.4% oxygen. Throughput ranged from 0.14 to 0.27 kg/hr depending on the variability in the waste material composition and density.

Meyer, M.L.

1991-12-31

105

Pyrochemical reduction of uranium dioxide and plutonium dioxide by lithium metal  

Microsoft Academic Search

The lithium reduction process has been developed to apply a pyrochemical recycle process for oxide fuels. This process uses lithium metal as a reductant to convert oxides of actinide elements to metal. Lithium oxide generated in the reduction would be dissolved in a molten lithium chloride bath to enhance reduction. In this work, the solubility of Li2O in LiCl was

T. Usami; M. Kurata; T. Inoue; H. E Sims; S. A Beetham; J. A Jenkins

2002-01-01

106

Spectroscopic investigations of neptunium`s and plutonium`s oxidation states in sol-gel glasses as a function of initial valance and thermal history  

SciTech Connect

Several oxidation states of neptunium and plutonium, Pu(III),Pu (IV), PU(VI), Np(IV), Np(V) and Np (VI), were studied in glasses prepared by a sol-gel technology. The oxidation state of these actinides was determined primarily by absorption spectrometry and followed as a function of the solidification process, subsequent aging and thermal treatments. It was determined that the initial oxidation state of the actinides in the starting solutions was essentially maintained through the solidification process to form the glasses. However, during densification and removal of residual solvents at elevated temperatures, both actinides in the different sol-gel products converted completely to their tetravalent states. These results are discussed in terms of our findings in comparable studies that only the tetravalent states of plutonium and neptunium are formed in glasses prepared by dissolving their dioxides in different molten- glass formulations.

Stump, N.A. [Winston-Salem State Univ., NC (United States). Dept. of Physical Sciences; Haire, R.G.; Dai, S. [Oak Ridge National Lab., TN (United States)

1996-12-01

107

Multi-generational stewardship of plutonium  

SciTech Connect

The post-cold war era has greatly enhanced the interest in the long-term stewardship of plutonium. The management of excess plutonium from proposed nuclear weapons dismantlement has been the subject of numerous intellectual discussions during the past several years. In this context, issues relevant to long-term management of all plutonium as a valuable energy resource are also being examined. While there are differing views about the future role of plutonium in the economy, there is a recognition of the environmental and health related problems and proliferation potentials of weapons-grade plutonium. The long-term management of plutonium as an energy resource will require a new strategy to maintain stewardship for many generations to come.

Pillay, K.K.S. [Los Alamos National Lab., NM (United States). Nuclear Materials Technology Div.

1997-10-01

108

Plutonium Immobilization Can Loading Concepts  

SciTech Connect

The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses five can loading conceptual designs and the lists the advantages and disadvantages for each concept. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas. The can loading welder and cutter are very similar to the existing Savannah River Site (SRS) FB-Line bagless transfer welder and cutter and thus they are a low priority development item.

Kriikku, E. [Westinghouse Savannah River Company, AIKEN, SC (United States); Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.; Rogers, L.; Fiscus, J.; Dyches, G.

1998-05-01

109

Alpha-plutonium's Grüneisen parameter  

NASA Astrophysics Data System (ADS)

Reported Grüneisen parameters ? of alpha-plutonium range from 3.0 to 9.6, which is remarkable because typical Grüneisen parameter uncertainty seldom exceeds ± 0.5. Our six new estimates obtained by different methods range from 3.2 to 9.6. The new estimates arise from Grüneisen's rule, from Einstein model and Debye model fits to low-temperature ?V/V, from the bulk modulus temperature dependence, from the zero-point-energy contribution to the bulk modulus, and from another Grüneisen relationship whereby ? is estimated from only the bulk modulus and volume changes with temperature (or pressure). We disregard several high estimates because of the itinerant-localized 5f-electron changes during temperature changes and pressure changes. Considering all these estimates, for alpha-plutonium, we recommend ? = 3.7 ± 0.4, slightly high compared with values for all elemental metals.

Ledbetter, Hassel; Lawson, Andrew; Migliori, Albert

2010-04-01

110

Alpha-plutonium's Grüneisen parameter.  

PubMed

Reported Grüneisen parameters ? of alpha-plutonium range from 3.0 to 9.6, which is remarkable because typical Grüneisen parameter uncertainty seldom exceeds ± 0.5. Our six new estimates obtained by different methods range from 3.2 to 9.6. The new estimates arise from Grüneisen's rule, from Einstein model and Debye model fits to low-temperature ?V/V, from the bulk modulus temperature dependence, from the zero-point-energy contribution to the bulk modulus, and from another Grüneisen relationship whereby ? is estimated from only the bulk modulus and volume changes with temperature (or pressure). We disregard several high estimates because of the itinerant-localized 5f-electron changes during temperature changes and pressure changes. Considering all these estimates, for alpha-plutonium, we recommend ? = 3.7 ± 0.4, slightly high compared with values for all elemental metals. PMID:21386421

Ledbetter, Hassel; Lawson, Andrew; Migliori, Albert

2010-04-28

111

Air transport of plutonium metal: content expansion initiative for the plutonium air transportable (PAT01) packaging  

SciTech Connect

The National Nuclear Security Administration (NNSA) has submitted an application to the Nuclear Regulatory Commission (NRC) for the air shipment of plutonium metal within the Plutonium Air Transportable (PAT-1) packaging. The PAT-1 packaging is currently authorized for the air transport of plutonium oxide in solid form only. The INMM presentation will provide a limited overview of the scope of the plutonium metal initiative and provide a status of the NNSA application to the NRC.

Caviness, Michael L [Los Alamos National Laboratory; Mann, Paul T [NNSA/ALBUQUERQUE; Yoshimura, Richard H [SNL

2010-01-01

112

Air transport of plutonium metal : content expansion initiative for the Plutonium Air Transportable (PAT-1) packaging.  

SciTech Connect

The National Nuclear Security Administration (NNSA) has submitted an application to the Nuclear Regulatory Commission (NRC) for the air shipment of plutonium metal within the Plutonium Air Transportable (PAT-1) packaging. The PAT-1 packaging is currently authorized for the air transport of plutonium oxide in solid form only. The INMM presentation will provide a limited overview of the scope of the plutonium metal initiative and provide a status of the NNSA application to the NRC.

Mann, Paul T. (National Nuclear Security Administration); Caviness, Michael L. (Los Alamos National Laboratory); Yoshimura, Richard Hiroyuki

2010-06-01

113

Screen for Carbon Dioxide.  

ERIC Educational Resources Information Center

Presents a set of laboratory experiments that can assist students in the detection of carbon dioxide. Offers a variation of the supported drop method of carbon dioxide detection that provides readily visible positive results. Includes background information on carbon dioxide. (ML)

Foster, John; And Others

1986-01-01

114

10 CFR 71.63 - Special requirement for plutonium shipments.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special requirement for plutonium shipments. 71.63 Section 71.63...Standards § 71.63 Special requirement for plutonium shipments. Shipments containing plutonium must be made with the contents in...

2011-01-01

115

10 CFR 71.63 - Special requirement for plutonium shipments.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Special requirement for plutonium shipments. 71.63 Section 71.63...Standards § 71.63 Special requirement for plutonium shipments. Shipments containing plutonium must be made with the contents in...

2012-01-01

116

10 CFR 71.63 - Special requirement for plutonium shipments.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Special requirement for plutonium shipments. 71.63 Section 71.63...Standards § 71.63 Special requirement for plutonium shipments. Shipments containing plutonium must be made with the contents in...

2013-01-01

117

10 CFR 71.63 - Special requirement for plutonium shipments.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Special requirement for plutonium shipments. 71.63 Section 71.63...Standards § 71.63 Special requirement for plutonium shipments. Shipments containing plutonium must be made with the contents in...

2014-01-01

118

10 CFR 71.63 - Special requirement for plutonium shipments.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special requirement for plutonium shipments. 71.63 Section 71.63...Standards § 71.63 Special requirement for plutonium shipments. Shipments containing plutonium must be made with the contents in...

2010-01-01

119

Plutonium Proliferation: The Achilles Heel of Disarmament  

Microsoft Academic Search

Plutonium is a byproduct of nuclear fission, and it is produced at the rate of about 70 metric tons a year in the world's nuclear power reactors. Concerns about civilian plutonium ran high in the 1970s and prompted enactment of the Nuclear Non-Proliferation Act of 1978 to give the United States a veto over separating plutonium from U.S.-supplied uranium fuel.

Leventhal

2001-01-01

120

PLUTONIUM METAL: OXIDATION CONSIDERATIONS AND APPROACH  

SciTech Connect

Plutonium is arguably the most unique of all metals when considered in the combined context of metallurgical, chemical, and nuclear behavior. Much of the research in understanding behavior and characteristics of plutonium materials has its genesis in work associated with nuclear weapons systems. However, with the advent of applications in fuel materials, the focus in plutonium science has been more towards nuclear fuel applications, as well as long term storage and disposition. The focus of discussion included herein is related to preparing plutonium materials to meet goals consistent with non-proliferation. More specifically, the emphasis is on the treatment of legacy plutonium, in primarily metallic form, and safe handling, packaging, and transport to meet non-proliferation goals of safe/secure storage. Elevated temperature oxidation of plutonium metal is the treatment of choice, due to extensive experiential data related to the method, as the oxide form of plutonium is one of only a few compounds that is relatively simple to produce, and stable over a large temperature range. Despite the simplicity of the steps required to oxidize plutonium metal, it is important to understand the behavior of plutonium to ensure that oxidation is conducted in a safe and effective manner. It is important to understand the effect of changes in environmental variables on the oxidation characteristics of plutonium. The primary purpose of this report is to present a brief summary of information related to plutonium metal attributes, behavior, methods for conversion to oxide, and the ancillary considerations related to processing and facility safety. The information provided is based on data available in the public domain and from experience in oxidation of such materials at various facilities in the United States. The report is provided as a general reference for implementation of a simple and safe plutonium metal oxidation technique.

Estochen, E.

2013-03-20

121

PROPRITS MAGNTIQUES ET STRUCTURE LECTRONIQUE DU PLUTONIUM  

E-print Network

699 PROPRI�T�S MAGN�TIQUES ET STRUCTURE �LECTRONIQUE DU PLUTONIUM J.-M. FOURNIER Centre d obtenus sur la susceptibilité magnétique du plutonium-03B1. Nous proposons ensuite un schéma de structure de bande que nous utilisons pour expliquer les anomalies d'autres propriétés physiques du plutonium

Paris-Sud XI, Université de

122

PLUTONIUM ALLOYS CONTAINING CONTROLLED AMOUNTS OF PLUTONIUM ALLOTROPES OBTAINED BY APPLICATION OF HIGH PRESSURES  

Microsoft Academic Search

A method is given for making stabilized plutonium alloys which are free ; of voids and cracks and have a controlled amount of plutonium allotropes. The ; steps include adding at least 4.5 at.% of hafnium, indium, or erbium to the ; melted plutonium metal, homogenizing the resulting alloy at a temperature of 450 ; deg C, cooling to room

R. O. Elliott; K. A. Jr. Gschneidner

1962-01-01

123

PLUTONIUM FUELS DEVELOPMENT, PLUTONIUM METALLURGY OPERATION QUARTERLY REPORT-JANUARY, FEBRUARY, MARCH 1958  

Microsoft Academic Search

The last two of four Zircaloy-clad capsules containing aluminum-; plutonium and aluminum-- silicon--plutonium were discharged from the MTR and are ; undergoing examination. These capsules withstood a fractional bunnout of ; plutonium atoms of 55 to 60% as determined by flux monitoring wires attached to ; the capsule holder. Additional capsules of these fuel alloys containing a higher ; concentration

Wick

1958-01-01

124

PLUTONIUM ALLOYS CONTAINING CONTROLLED AMOUNTS OF PLUTONIUM ALLOTROPES OBTAINED BY APPLICATION OF HIGH PRESSURES  

Microsoft Academic Search

A method of making stabilized plutonium alloys which are free of voids ; and cracks and have a controlled amount of plutonium allotropes is described. ; The steps include adding at least 4.5 at.% of hafnium, indium, or erbium to the ; melted plutonium metal, homogenizing the resulting alloy at a temperature of 450 ; deg C, cooling to room

R. O. Elliott; K. A. Jr. Gschneidner

1962-01-01

125

Thorium plutonium (TREX) fuel for weapons-grade plutonium disposition in pressurized water reactors  

Microsoft Academic Search

The goal of this study was to create a pressurized water reactor (PWR) reactor assembly (17 x 17) that would burn weapons-grade plutonium (WGP). Current designs of mixed-oxide (MOX) fuels combine WGP with uranium as the fuel. MOX fuel assemblies will destroy plutonium, but only 40 to 50% of the plutonium present in the fuel. This percentage is limited by

C. Comfort; C. Ferguson; S. Klima; D. E. Lilly; F. Rahnema

1996-01-01

126

The Vapor Pressure of Plutonium Halides  

Microsoft Academic Search

Vapor pressure measurements have been made with three halides of plutonium by a modification of the Knudsen effusion method. Measurements with solid plutonium trifluoride from 1200°K to 1440°K give the vapor pressure-temperature relation log10pmm=12.468–21,120\\/T. Measurements with liquid plutonium trifluoride from 1440°K to 1770°K give log10pmm=11.273–19,400\\/T. Measurements with solid plutonium trichloride from 850°K to 1007°K give log10pmm=12.726–15,910\\/T; with liquid trichloride from

T. E. Phipps; G. W. Sears; R. L. Seifert; O. C. Simpson

1950-01-01

127

A summary of volatile impurity measurements and gas generation studies on MISSTD-1, a high-purity plutonium oxide produced by low-temperature calcination of plutonium oxalate  

SciTech Connect

Plutonium dioxide of high specific surface area was subjected to long-term tests of gas generation in sealed containers. The material preparation and the storage conditions were outside the bounds of acceptable parameters defined by DOE-STD-3013-2012 in that the material was stabilized to a lower temperature than required and had higher moisture content than allowed. The data provide useful information for better defining the bounding conditions for safe storage. Net increases in internal pressure and transient increases in H{sub 2} and O{sub 2} were observed, but were well within the bounds of gas compositions previously shown to not threaten integrity of 3013 containers.

Berg, John M. [Los Alamos National Laboratory; Narlesky, Joshua E. [Los Alamos National Laboratory; Veirs, Douglas K. [Los Alamos National Laboratory

2012-06-08

128

Pyrochemical process for extracting plutonium from an electrolyte salt  

DOEpatents

A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium from electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

Mullins, Lawrence J. (Los Alamos, NM); Christensen, Dana C. (Los Alamos, NM)

1984-01-01

129

Pyrochemical process for extracting plutonium from an electrolyte salt  

DOEpatents

A pyrochemical process for extracting plutonium from a plutonium-bearing salt is disclosed. The process is particularly useful in the recovery of plutonium for electrolyte salts which are left over from the electrorefining of plutonium. In accordance with the process, the plutonium-bearing salt is melted and mixed with metallic calcium. The calcium reduces ionized plutonium in the salt to plutonium metal, and also causes metallic plutonium in the salt, which is typically present as finely dispersed metallic shot, to coalesce. The reduced and coalesced plutonium separates out on the bottom of the reaction vessel as a separate metallic phase which is readily separable from the overlying salt upon cooling of the mixture. Yields of plutonium are typically on the order of 95%. The stripped salt is virtually free of plutonium and may be discarded to low-level waste storage.

Mullins, L.J.; Christensen, D.C.

1982-09-20

130

Plutonium Immobilization Project -- Robotic canister loading  

SciTech Connect

The Plutonium Immobilization Program (PIP) is a joint venture between the Savannah River Site, Lawrence Livermore National Laboratory, Argonne National Laboratory, and Pacific Northwest National Laboratory. When operational in 2008, the PIP will fulfill the nation's nonproliferation commitment by placing surplus weapons-grade plutonium in a permanently stable ceramic form.

Hamilton, L.

2000-04-28

131

Accelerator mass spectrometry of plutonium isotopes  

Microsoft Academic Search

The feasibility of measuring plutonium isotope ratios by accelerator mass spectrometry has been demonstrated. Measurements on a test sample of known composition and on a blank showed that isotope ratios could be determined quantitatively, and that the present limit of detection by AMS is ? 106 atoms of plutonium. For 239Pu, this limit is at least two orders of magnitude

L. K. Fifield; R. G. Cresswell; M. L. di Tada; T. R. Ophel; J. P. Day; A. P. Clacher; S. J. King; N. D. Priest

1996-01-01

132

Corrosive gas generation potential from chloride salt radiolysis in plutonium environments  

SciTech Connect

The specific goal of this project was to evaluate the magnitude and practical significance of radiation effects involving mixtures of chloride salts and plutonium dioxide (PuO{sub 2}) sealed in stainless steel containers and stored for up to 50 yr, after stabilization at 950 C and packaging according to US Department of Energy (DOE) standards. The potential for generating chemically aggressive molecular chlorine (and hydrogen chloride by interaction with adsorbed water or hydrogen gas) by radiolysis of chloride ions was studied. To evaluate the risks, an annotated bibliography on chloride salt radiolysis was created with emphasis on effects of plutonium alpha radiation. The authors present data from the material identification and surveillance (MIS) project obtained from examination and analysis of representative PuO{sub 2} items from various DOE sites, including the headspace gas analysis data of sealed mixtures of PuO{sub 2} and chloride salts following long-term storage.

Tandon, L.; Allen, T.H.; Mason, R.E.; Penneman, R.A.

1999-07-01

133

REMOVAL OF LEGACY PLUTONIUM MATERIALS FROM SWEDEN  

SciTech Connect

U.S. Department of Energy’s National Nuclear Security Administration (NNSA) Office of Global Threat Reduction (GTRI) recently removed legacy plutonium materials from Sweden in collaboration with AB SVAFO, Sweden. This paper details the activities undertaken through the U.S. receiving site (Savannah River Site (SRS)) to support the characterization, stabilization, packaging and removal of legacy plutonium materials from Sweden in 2012. This effort was undertaken as part of GTRI’s Gap Materials Program and culminated with the successful removal of plutonium from Sweden as announced at the 2012 Nuclear Security Summit. The removal and shipment of plutonium materials to the United States was the first of its kind under NNSA’s Global Threat Reduction Initiative. The Environmental Assessment for the U.S. receipt of gap plutonium material was approved in May 2010. Since then, the multi-year process yielded many first time accomplishments associated with plutonium packaging and transport activities including the application of the of DOE-STD-3013 stabilization requirements to treat plutonium materials outside the U.S., the development of an acceptance criteria for receipt of plutonium from a foreign country, the development and application of a versatile process flow sheet for the packaging of legacy plutonium materials, the identification of a plutonium container configuration, the first international certificate validation of the 9975 shipping package and the first intercontinental shipment using the 9975 shipping package. This paper will detail the technical considerations in developing the packaging process flow sheet, defining the key elements of the flow sheet and its implementation, determining the criteria used in the selection of the transport package, developing the technical basis for the package certificate amendment and the reviews with multiple licensing authorities and most importantly integrating the technical activities with the Swedish partners.

Dunn, Kerry A. [Savannah River National Laboratory; Bellamy, J. Steve [Savannah River National Laboratory; Chandler, Greg T. [Savannah River National Laboratory; Iyer, Natraj C. [U.S. Department of Energy, National Nuclear Security Administration, Office of; Koenig, Rich E.; Leduc, D. [Savannah River National Laboratory; Hackney, B. [Savannah River National Laboratory; Leduc, Dan R. [Savannah River National Laboratory

2013-08-18

134

The carbon dioxide cycle  

USGS Publications Warehouse

The seasonal CO2 cycle on Mars refers to the exchange of carbon dioxide between dry ice in the seasonal polar caps and gaseous carbon dioxide in the atmosphere. This review focuses on breakthroughs in understanding the process involving seasonal carbon dioxide phase changes that have occurred as a result of observations by Mars Global Surveyor. ?? 2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

James, P.B.; Hansen, G.B.; Titus, T.N.

2005-01-01

135

Plutonium Uptake and Distribution in Mammalian Cells: Molecular vs Polymeric Plutonium  

PubMed Central

Purpose To study the cellular responses to molecular and polymeric forms of plutonium using PC12 cells derived from rat adrenal glands. Materials and methods Serum starved PC12 cells were exposed to polymeric and molecular forms of plutonium for three hours. Cells were washed with 10 mM EGTA, 100 mM NaCl at pH 7.4 to remove surface sorbed plutonium. Localization of plutonium in individual cell was quantitatively analyzed by synchrotron X-ray fluorescence (XRF) microscopy. Results Molecular plutonium complexes introduced to cell growth media in the form of NTA, citrate, or transferrin complexes were taken up by PC12 cells, and mostly co-localized with iron within the cells. Polymeric plutonium prepared separately was not internalized by PC12 cells but it was always found on the cell surface as big agglomerates; however polymeric plutonium formed in situ was mostly found within the cells as agglomerates. Conclusions PC12 cells can differentiate molecular and polymeric forms of plutonium. Molecular plutonium is taken up by PC12 cells and mostly co-localized with iron but aged polymeric plutonium is not internalized by the cells. PMID:21770702

ARYAL, BAIKUNTHA P.; GORMAN-LEWIS, DREW; PAUNESKU, TATJANA; WILSON, RICHARD E.; LAI, BARRY; VOGT, STEFAN; WOLOSCHAK, GAYLE E.; JENSEN, MARK P.

2013-01-01

136

Progress in the studies of the advanced plutonium fuel assembly  

Microsoft Academic Search

A new assembly concept, designated APA (for Advanced Plutonium fuel Assembly), should make it possible to multi-recycle plutonium in pressurized water reactors. The basic idea is founded on the manufacture of a large plutonium thin annular fuel rod with an inert support, cooled on both faces. The absence of plutonium generation, combined with moderate fuel temperature should make it possible

A. Puill; J. Bergeron; M. Rohart; S. Aniel-Buchheit; A. Bergeron; P. Matheron

2001-01-01

137

Temperature VS Carbon Dioxide  

NSDL National Science Digital Library

In this activity, students examine the relationship between carbon dioxide levels and global temperature change by studying a graph of these two variables. They will discover that by using data from ice cores, scientists can determine temperature and carbon dioxide levels in the air as far back as a hundred thousand years in the past. The students try to predict which variable is the independent one and then make a graph of temperature change and carbon dioxide levels. After making their graph, students describe the relationship between temperature and carbon dioxide levels in the atmosphere to determine if their predictions were correct.

138

Plutonium Immobilization Can Loading Conceptual Design  

SciTech Connect

'The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization can loading conceptual design and includes a process block diagram, process description, preliminary equipment specifications, and several can loading issues. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.'

Kriikku, E.

1999-05-13

139

Weapons-grade plutonium dispositioning. Volume 4. Plutonium dispositioning in light water reactors  

SciTech Connect

This study is in response to a request by the Reactor Panel Subcommittee of the National Academy of Sciences (NAS) Committee on International Security and Arms Control (CISAC) to evaluate the feasibility of using plutonium fuels (without uranium) for disposal in existing conventional or advanced light water reactor (LWR) designs and in low temperature/pressure LWR designs that might be developed for plutonium disposal. Three plutonium-based fuel forms (oxides, aluminum metallics, and carbides) are evaluated for neutronic performance, fabrication technology, and material and compatibility issues. For the carbides, only the fabrication technologies are addressed. Viable plutonium oxide fuels for conventional or advanced LWRs include plutonium-zirconium-calcium oxide (PuO{sub 2}-ZrO{sub 2}-CaO) with the addition of thorium oxide (ThO{sub 2}) or a burnable poison such as erbium oxide (Er{sub 2}O{sub 3}) or europium oxide (Eu{sub 2}O{sub 3}) to achieve acceptable neutronic performance. Thorium will breed fissile uranium that may be unacceptable from a proliferation standpoint. Fabrication of uranium and mixed uranium-plutonium oxide fuels is well established; however, fabrication of plutonium-based oxide fuels will require further development. Viable aluminum-plutonium metallic fuels for a low temperature/pressure LWR include plutonium aluminide in an aluminum matrix (PuAl{sub 4}-Al) with the addition of a burnable poison such as erbium (Er) or europium (Eu). Fabrication of low-enriched plutonium in aluminum-plutonium metallic fuel rods was initially established 30 years ago and will require development to recapture and adapt the technology to meet current environmental and safety regulations. Fabrication of high-enriched uranium plate fuel by the picture-frame process is a well established process, but the use of plutonium would require the process to be upgraded in the United States to conform with current regulations and minimize the waste streams.

Sterbentz, J.W.; Olsen, C.S.; Sinha, U.P.

1993-06-01

140

XPS-AES characterization of plutonium oxides and oxide carbide. The existence of plutonium monoxide  

Microsoft Academic Search

The plutonium-oxygen phase diagrams has been clarified by XPS and AES results which show that three oxygen-containing plutonium phases, PuOâ, ..cap alpha..-PuâOâ, and PuO\\/sub x\\/C\\/sub y\\/, are successively formed when oxide-coated plutonium metal is heated in vacuo to 500°C. Formation of the oxide carbide is evidenced by the fact that a shift in the Pu(4fââ) binding energy is coincident with

D. T. Larson; John M. Haschke

1981-01-01

141

Hydride-catalyzed corrosion of plutonium by air: Initiation by plutonium monoxide monohydride  

Microsoft Academic Search

Chemistry and kinetics of air reactions with plutonium monoxide monohydride (PuOH) and with mixtures of the oxide hydride and plutonium metal are defined by results of pressure-volume-temperature (PVT) measurements. Test with specimens prepared by total and partial corrosion of plutonium in 0.05 M sodium chloride solution show that reaction of residual water continues to generate Hâ after liquid water is

T. H. Allen; J. M. Haschke

1998-01-01

142

Estimated discard limits for plutonium-238 recovery processing in the plutonium processing building  

Microsoft Academic Search

This manual is intended as a basis for plutonium-238 recovery costs and as a guide for removal of plutonium-bearing wastes from the gloveboxes to be safely and economically discarded. Waste materials contaminated with plutonium-238 are generated from in-house production, analytical, process development, recovery and receipts from off-site. The contaminated materials include paper, rags, alpha-box gloves, piping, valves, filters, etc. General

D. F. Luthy; W. H. Bond

1975-01-01

143

Carbon Dioxide Fountain  

ERIC Educational Resources Information Center

This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

Kang, Seong-Joo; Ryu, Eun-Hee

2007-01-01

144

Carbon Dioxide Emission Estimates  

NSDL National Science Digital Library

The Carbon Dioxide Information Analysis Center of the Oak Ridge National Laboratory provides this new data on carbon dioxide emissions from fossil fuel burning, hydraulic cement production, and gas flaring in 1995. Data for one degree grid cells can be downloaded from the site in addition to code for analysis of the data.

145

Production of Carbon Dioxide  

NSDL National Science Digital Library

In this chemistry activity, learners use common chemicals to produce carbon dioxide and observe its properties. This resource includes brief questions for learners to answer after the experiment. Use this activity to introduce learners to carbon dioxide and its use as a fire extinguisher. Note: this activity involves an open flame.

The Science House

2014-01-28

146

PLUTONIUM METALLOGRAPHY AT LOS ALAMOS  

SciTech Connect

From early days of the Manhattan program to today, scientists and engineers have continued to investigate the metallurgical properties of plutonium (Pu). Although issues like aging was not a concern to the early pioneers, today the reliability of our aging stockpile is of major focus. And as the country moves toward a new generation of weapons similar problems that the early pioneers faced such as compatibility, homogeneity and malleability have come to the forefront. And metallography will continue to be a principle tool for the resolution of old and new issues. Standard metallographic techniques are used for the preparation of plutonium samples. The samples are first cut with a slow speed idamond saw. After mounting in Epon 815 epoxy resin, the samples are ground through 600 grit silicon carbide paper. PF 5070 (a Freon substitute) is used as a coolant, lubricant, and solvent for most operations. Rough mechanical polished is done with 9-{mu} diamond using a nap less cloth, for example nylon or cotton. Final polish is done with 1-{mu} diamond on a nappy cloth such as sylvet. Ethyl alcohol is then used ultrasonically to clean the samples before electro polishing. The sample is then electro-polished and etched in an electrolyte containing 10% nitric acid, and 90% dimethyleneformalmide. Ethyl alcohol is used as a final cleaning agent. Although standard metallographic preparation techniques are used, there are several reasons why metallography of Pu is difficult and challenging. Firstly, because of the health hazards associated with its radioactive properties, sample preparation is conducted in glove boxes. Figure 1 shows the metallography line, in an R and D facility. Since they are designed to be negative in pressure to the laboratory, cross-contamination of abrasives is a major problem. In addition, because of safety concerns and waste issues, there is a limit to the amount of solvent that can be used. Secondly, Pu will readily hydride or oxidize when in contact with metallographic polishing lubricants, solvents, or chemicals. And water being one of the most reactive solutions, is not used in the preparation. Figure 2 shows an example of a plutonium sample in which an oxide film has formed on the surface due to overexposure to solutions. it has been noted that nucleation of the hydride/oxide begins around inclusions and samples with a higher concentration of impurities seem to be more susceptible to this reaction. Figure 3 shows examples of small oxide rings, forming around inclusions. Lastly, during the cutting, grinding, or polishing process there is enough stress induced in the sample that the surface can transform from the soft face-centered-cubic delta phase (30 HV) to the strain-induced monoclinic alpha{prime} phase (300 HV). Figure 4 and 5 shows cross-sectional views of samples in which one was cut using a diamond saw and the other was processed through 600 grit. The white layers on the edges is the strain induced alpha{prime} phase. The 'V' shape indentation in Figure 5 was caused by a coarser abrasive which resulted in transformations to a depth of approximately 20 {micro}m. Another example of the transformation sensitivity of plutonium can be seen in Figure 6, in which the delta phase has partly transformed to alpha{prime} during micro hardness indentation.

PEREYRA, RAMIRO A. [Los Alamos National Laboratory; LOVATO, DARRYL [Los Alamos National Laboratory

2007-01-08

147

A Plutonium Storage Container Pressure Measurement Technique  

Microsoft Academic Search

Plutonium oxide and metal awaiting final disposition are currently stored at the Savannah River Site in crimp sealed food pack cans. Surveillances to ensure continued safe storage of the cans include periodic lid deflection measurements using a mechanical device.

Grim

2002-01-01

148

Interaction between stainless steel and plutonium metal  

SciTech Connect

Long-term storage of excess plutonium is of great concern in the U.S. as well as abroad. The current accepted configuration involves intimate contact between the stored material and an iron-bearing container such as stainless steel. While many safety scenario studies have been conducted and used in the acceptance of stainless steel containers, little information is available on the physical interaction at elevated temperatures between certain forms of stored material and the container itself. The bulk of the safety studies has focused on the ability of a package to keep the primary stainless steel containment below the plutonium-iron eutectic temperature of approximately 410 C. However, the interactions of plutonium metal with stainless steel have been of continuing interest. This paper reports on a scoping study investigating the interaction between stainless steel and plutonium metal in a pseudo diffusion couple at temperatures above the eutectic melt-point.

Dunwoody, John T [Los Alamos National Laboratory; Mason, Richard E [Los Alamos National Laboratory; Freibert, Franz J [Los Alamos National Laboratory; Willson, Stephen P [Los Alamos National Laboratory; Veirs, Douglas K [Los Alamos National Laboratory; Worl, Laura A [Los Alamos National Laboratory; Archuleta, Alonso [Los Alamos National Laboratory; Conger, Donald J [Los Alamos National Laboratory

2010-01-01

149

Plutonium finishing plant dangerous waste training plan  

SciTech Connect

This training plan describes general requirements, worker categories, and provides course descriptions for operation of the Plutonium Finish Plant (PFP) waste generation facilities, permitted treatment, storage and disposal (TSD) units, and the 90-Day Accumulation Areas.

ENTROP, G.E.

1999-05-24

150

Analysis of plutonium in soil samples  

PubMed

Procedures for analysis of plutonium in soil samples were developed using anion exchange as a purification technique. Special attention was paid to removing impurities of 228Th which interferes in 238Pu determination by alpha spectrometry. Two anion-exchange methods were compared. The determination of plutonium in soil involves the conversion of soil samples to acid-soluble form. Two methods for the extraction of plutonium from a natural reference soil were compared. The first method (a direct digestion in nitric acid) is suitable for the determination of plutonium in large amounts of sample. The second method involves microwave digestion of soil (5 g) with a mixture of HNO3, HCl and HF, and is suitable for saving time in routine determinations. Activities calculated with a reference soil matrix were in good agreement with the reference value. The microwave digestion method was applied in a study of different soil samples, and recoveries ranged between 20% and 50%. PMID:10879871

Rubio Montero MP; Martin Sanchez A; Crespo Vazquez MT; Gascon Murillo JL

2000-07-01

151

Explosive properties of reactor?grade plutonium  

Microsoft Academic Search

The following discussion focuses on the question of whether a terrorist organization or a threshold state could make use of plutonium recovered from light?water?reactor fuel to construct a nuclear explosive device having a significantly damaging yield. Questions persist in some nonproliferation policy circles as to whether a bomb could be made from reactor?grade plutonium of high burn?up, and if so,

J. Carson Marka

1993-01-01

152

Complementary technologies for verification of excess plutonium  

SciTech Connect

Three complementary measurement technologies have been identified as candidates for use in the verification of excess plutonium of weapons origin. These technologies: high-resolution gamma-ray spectroscopy, neutron multiplicity counting, and low-resolution gamma-ray spectroscopy, are mature, robust technologies. The high-resolution gamma-ray system, Pu-600, uses the 630--670 keV region of the emitted gamma-ray spectrum to determine the ratio of {sup 240}Pu to {sup 239}Pu. It is useful in verifying the presence of plutonium and the presence of weapons-grade plutonium. Neutron multiplicity counting is well suited for verifying that the plutonium is of a safeguardable quantity and is weapons-quality material, as opposed to residue or waste. In addition, multiplicity counting can independently verify the presence of plutonium by virtue of a measured neutron self-multiplication and can detect the presence of non-plutonium neutron sources. The low-resolution gamma-ray spectroscopic technique is a template method that can provide continuity of knowledge that an item that enters the a verification regime remains under the regime. In the initial verification of an item, multiple regions of the measured low-resolution spectrum form a unique, gamma-radiation-based template for the item that can be used for comparison in subsequent verifications. In this paper the authors discuss these technologies as they relate to the different attributes that could be used in a verification regime.

Langner, , D.G.; Nicholas, N.J.; Ensslin, N.; Fearey, B.L. [Los Alamos National Lab., NM (United States); Mitchell, D.J.; Marlow, K.W. [Sandia National Lab., Albuquerque, NM (United States); Luke, S.J.; Gosnell, T.B. [Lawrence Livermore National Lab., CA (United States)

1998-12-31

153

Plutonium Finishing Plant safety evaluation report  

SciTech Connect

The Plutonium Finishing Plant (PFP) previously known as the Plutonium Process and Storage Facility, or Z-Plant, was built and put into operation in 1949. Since 1949 PFP has been used for various processing missions, including plutonium purification, oxide production, metal production, parts fabrication, plutonium recovery, and the recovery of americium (Am-241). The PFP has also been used for receipt and large scale storage of plutonium scrap and product materials. The PFP Final Safety Analysis Report (FSAR) was prepared by WHC to document the hazards associated with the facility, present safety analyses of potential accident scenarios, and demonstrate the adequacy of safety class structures, systems, and components (SSCs) and operational safety requirements (OSRs) necessary to eliminate, control, or mitigate the identified hazards. Documented in this Safety Evaluation Report (SER) is DOE`s independent review and evaluation of the PFP FSAR and the basis for approval of the PFP FSAR. The evaluation is presented in a format that parallels the format of the PFP FSAR. As an aid to the reactor, a list of acronyms has been included at the beginning of this report. The DOE review concluded that the risks associated with conducting plutonium handling, processing, and storage operations within PFP facilities, as described in the PFP FSAR, are acceptable, since the accident safety analyses associated with these activities meet the WHC risk acceptance guidelines and DOE safety goals in SEN-35-91.

Not Available

1995-01-01

154

A DGT technique for plutonium bioavailability measurements.  

PubMed

The toxicity of heavy metals in natural waters is strongly dependent on the local chemical environment. Assessing the bioavailability of radionuclides predicts the toxic effects to aquatic biota. The technique of diffusive gradients in thin films (DGT) is largely exploited for bioavailability measurements of trace metals in waters. However, it has not been applied for plutonium speciation measurements yet. This study investigates the use of DGT technique for plutonium bioavailability measurements in chemically different environments. We used a diffusion cell to determine the diffusion coefficients (D) of plutonium in polyacrylamide (PAM) gel and found D in the range of 2.06-2.29 × 10(-6) cm(2) s(-1). It ranged between 1.10 and 2.03 × 10(-6) cm(2) s(-1) in the presence of fulvic acid and in natural waters with low DOM. In the presence of 20 ppm of humic acid of an organic-rich soil, plutonium diffusion was hindered by a factor of 5, with a diffusion coefficient of 0.50 × 10(-6) cm(2) s(-1). We also tested commercially available DGT devices with Chelex resin for plutonium bioavailability measurements in laboratory conditions and the diffusion coefficients agreed with those from the diffusion cell experiments. These findings show that the DGT methodology can be used to investigate the bioaccumulation of the labile plutonium fraction in aquatic biota. PMID:25141175

Cusnir, Ruslan; Steinmann, Philipp; Bochud, François; Froidevaux, Pascal

2014-09-16

155

Preparation and characterization of manganese dioxide impregnated resin for radionuclide pre-concentration.  

PubMed

An easy and reproducible preparation of manganese dioxide impregnated resin of homogeneous particles has been described. The characteristics of radium, thorium, uranium and plutonium uptake (pH dependency, kinetic studies and matrix dependency) have been determined in batch mode. The resin due to its high efficiency for radium, uranium and thorium at neutral pH values can be an effective tool for radionuclide pre-concentration from liquid samples even with high dissolved solid content. PMID:17590345

Varga, Zsolt

2007-10-01

156

What is plutonium stabilization, and what is safe storage of plutonium?  

Microsoft Academic Search

The end of the cold war has resulted in the shutdown of nuclear weapons production and the start of dismantlement of significant numbers of nuclear weapons. This, in turn, is creating an inventory of plutonium requiring interim and long-term storage. A key question is, ``What is required for safe, multidecade, plutonium storage?`` The requirements for storage, in turn, define what

1995-01-01

157

Development of plutonium recycle in thermal reactors. Evaluation of plutonium recycle in pressurized water reactors  

Microsoft Academic Search

An evaluation of the utilization of plutonium recycle fuel in the ; Obrigheim power reactor was performed in order to study the characteristics of ; typical large PWR's operated with plutonium recycle fuel. The evaluation ; included nuclear characteristics, fuel management, a thermal-hydraulic analysis, ; and an economic analysis. (JWR)

J. R. Tomonto; J. S. Tulenko; J. Fiscella; J. Ray

1969-01-01

158

Decay Heat Calculations for PWR and BWR Assemblies Fueled with Uranium and Plutonium Mixed Oxide Fuel using SCALE  

SciTech Connect

In currently operating commercial nuclear power plants (NPP), there are two main types of nuclear fuel, low enriched uranium (LEU) fuel, and mixed-oxide uranium-plutonium (MOX) fuel. The LEU fuel is made of pure uranium dioxide (UO{sub 2} or UOX) and has been the fuel of choice in commercial light water reactors (LWRs) for a number of years. Naturally occurring uranium contains a mixture of different uranium isotopes, primarily, {sup 235}U and {sup 238}U. {sup 235}U is a fissile isotope, and will readily undergo a fission reaction upon interaction with a thermal neutron. {sup 235}U has an isotopic concentration of 0.71% in naturally occurring uranium. For most reactors to maintain a fission chain reaction, the natural isotopic concentration of {sup 235}U must be increased (enriched) to a level greater than 0.71%. Modern nuclear reactor fuel assemblies contain a number of fuel pins potentially having different {sup 235}U enrichments varying from {approx}2.0% to {approx}5% enriched in {sup 235}U. Currently in the United States (US), all commercial nuclear power plants use UO{sub 2} fuel. In the rest of the world, UO{sub 2} fuel is still commonly used, but MOX fuel is also used in a number of reactors. MOX fuel contains a mixture of both UO{sub 2} and PuO{sub 2}. Because the plutonium provides the fissile content of the fuel, the uranium used in MOX is either natural or depleted uranium. PuO{sub 2} is added to effectively replace the fissile content of {sup 235}U so that the level of fissile content is sufficiently high to maintain the chain reaction in an LWR. Both reactor-grade and weapons-grade plutonium contains a number of fissile and non-fissile plutonium isotopes, with the fraction of fissile and non-fissile plutonium isotopes being dependent on the source of the plutonium. While only RG plutonium is currently used in MOX, there is the possibility that WG plutonium from dismantled weapons will be used to make MOX for use in US reactors. Reactor-grade plutonium in MOX fuel is generally obtained from reprocessed irradiated nuclear fuel, whereas weapons-grade plutonium is obtained from decommissioned nuclear weapons material and thus has a different plutonium (and other actinides) concentration. Using MOX fuel instead of UOX fuel has potential impacts on the neutronic performance of the nuclear fuel and the design of the nuclear fuel must take these differences into account. Each of the plutonium sources (RG and WG) has different implications on the neutronic behavior of the fuel because each contains a different blend of plutonium nuclides. The amount of heat and the number of neutrons produced from fission of plutonium nuclides is different from fission of {sup 235}U. These differences in UOX and MOX do not end at discharge of the fuel from the reactor core - the short- and long-term storage of MOX fuel may have different requirements than UOX fuel because of the different discharged fuel decay heat characteristics. The research documented in this report compares MOX and UOX fuel during storage and disposal of the fuel by comparing decay heat rates for typical pressurized water reactor (PWR) and boiling water reactor (BWR) fuel assemblies with and without weapons-grade (WG) and reactor-grade (RG) MOX fuel.

Ade, Brian J [ORNL; Gauld, Ian C [ORNL

2011-10-01

159

Carbon dioxide removal process  

DOEpatents

A process and apparatus for separating carbon dioxide from gas, especially natural gas, that also contains C.sub.3+ hydrocarbons. The invention uses two or three membrane separation steps, optionally in conjunction with cooling/condensation under pressure, to yield a lighter, sweeter product natural gas stream, and/or a carbon dioxide stream of reinjection quality and/or a natural gas liquids (NGL) stream.

Baker, Richard W.; Da Costa, Andre R.; Lokhandwala, Kaaeid A.

2003-11-18

160

Comparison of sample preparation methods for reliable plutonium and neptunium urinalysis using automatic extraction chromatography.  

PubMed

This paper describes improvement and comparison of analytical methods for simultaneous determination of trace-level plutonium and neptunium in urine samples by inductively coupled plasma mass spectrometry (ICP-MS). Four sample pre-concentration techniques, including calcium phosphate, iron hydroxide and manganese dioxide co-precipitation and evaporation were compared and the applicability of different techniques was discussed in order to evaluate and establish the optimal method for in vivo radioassay program. The analytical results indicate that the various sample pre-concentration approaches afford dissimilar method performances and care should be taken for specific experimental parameters for improving chemical yields. The best analytical performances in terms of turnaround time (6h) and chemical yields for plutonium (88.7 ± 11.6%) and neptunium (94.2 ± 2.0%) were achieved by manganese dioxide co-precipitation. The need of drying ashing (? 7h) for calcium phosphate co-precipitation and long-term aging (5d) for iron hydroxide co-precipitation, respectively, rendered time-consuming analytical protocols. Despite the fact that evaporation is also somewhat time-consuming (1.5d), it endows urinalysis methods with better reliability and repeatability compared with co-precipitation techniques. In view of the applicability of different pre-concentration techniques proposed previously in the literature, the main challenge behind relevant method development is pointed to be the release of plutonium and neptunium associated with organic compounds in real urine assays. In this work, different protocols for decomposing organic matter in urine were investigated, of which potassium persulfate (K2S2O8) treatment provided the highest chemical yield of neptunium in the iron hydroxide co-precipitation step, yet, the occurrence of sulfur compounds in the processed sample deteriorated the analytical performance of the ensuing extraction chromatographic separation with chemical yields of ? 50%. PMID:25059133

Qiao, Jixin; Xu, Yihong; Hou, Xiaolin; Miró, Manuel

2014-10-01

161

71. INTERIOR, BUILDING 272 (PLUTONIUM STORAGE BUILDING) LOOKING NORTHEAST INTO ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

71. INTERIOR, BUILDING 272 (PLUTONIUM STORAGE BUILDING) LOOKING NORTHEAST INTO PLUTONIUM STORAGE ROOM SHOWING CUBICLES FOR STORAGE. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

162

69. INTERIOR, BUILDING 272 (PLUTONIUM STORAGE BUILDING) LOOKING SOUTHWEST THROUGH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

69. INTERIOR, BUILDING 272 (PLUTONIUM STORAGE BUILDING) LOOKING SOUTHWEST THROUGH DOOR-WAY INTO PLUTONIUM STORAGE AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

163

16. VIEW OF GLOVE BOX WORKSTATIONS WITHIN THE PLUTONIUM BUTTON ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. VIEW OF GLOVE BOX WORKSTATIONS WITHIN THE PLUTONIUM BUTTON BREAKOUT ROOM. (9/82) - Rocky Flats Plant, Plutonium Recovery Facility, Northwest portion of Rocky Flats Plant, Golden, Jefferson County, CO

164

17. VIEW OF THE FIRST PLUTONIUM BUTTON PRODUCED FROM THE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. VIEW OF THE FIRST PLUTONIUM BUTTON PRODUCED FROM THE BUILDING 371 AQUEOUS RECOVERY OPERATION. (9/30/83) - Rocky Flats Plant, Plutonium Recovery Facility, Northwest portion of Rocky Flats Plant, Golden, Jefferson County, CO

165

The design and evaluation of an international plutonium storage system  

E-print Network

To address the proliferation risk of separated plutonium, a technical and institutional design of an international plutonium storage system (IPSS) is presented. The IPSS is evaluated from two perspectives: its ability to ...

Bae, Eugene

2001-01-01

166

10 CFR 71.88 - Air transport of plutonium.  

Code of Federal Regulations, 2010 CFR

...to the activity concentration values for plutonium specified in Appendix A, Table A-2, of this part, and in which the radioactivity is essentially uniformly distributed; or (3) The plutonium is shipped in a single package containing no more than...

2010-01-01

167

10 CFR 71.88 - Air transport of plutonium.  

Code of Federal Regulations, 2013 CFR

...to the activity concentration values for plutonium specified in Appendix A, Table A-2, of this part, and in which the radioactivity is essentially uniformly distributed; or (3) The plutonium is shipped in a single package containing no more than...

2013-01-01

168

10 CFR 71.88 - Air transport of plutonium.  

Code of Federal Regulations, 2012 CFR

...to the activity concentration values for plutonium specified in Appendix A, Table A-2, of this part, and in which the radioactivity is essentially uniformly distributed; or (3) The plutonium is shipped in a single package containing no more than...

2012-01-01

169

10 CFR 71.88 - Air transport of plutonium.  

Code of Federal Regulations, 2011 CFR

...to the activity concentration values for plutonium specified in Appendix A, Table A-2, of this part, and in which the radioactivity is essentially uniformly distributed; or (3) The plutonium is shipped in a single package containing no more than...

2011-01-01

170

Dispersion of plutonium from contaminated pond sediments  

USGS Publications Warehouse

Sediment-water distributions of plutonium as a function of pH and contact time are investigated in a holding pond at the Rocky Flats plant of the Department of Energy. Although plutonium has been shown to sorb from natural waters onto sediments, the results of this study indicate that under the proper conditions it can be redispersed at pH 9 and above. Concentrations greater than 900 pCi Pu/L result after 34 h contact at pH 11 or 12 and the distribution coefficient, defined as the ratio of concentration in the sediment to that in the liquid, decreases from 1.1 ?? 105 at pH 7 to 1.2 ?? 103 at pH 11. The plutonium is probably dispersed as discrete colloids or as hydrolytic species adsorbed onto colloidal sediment particles whose average size decreases with increasing pH above pH 9. About 5% of the total plutonium is dispersed at pH 12, and the dispersion seems to readsorb on the sediment with time. Consequently, migration of plutonium from the pond should be slow, and it would be difficult to remove this element completely from pond sediment by leaching with high pH solutions. ?? 1978 American Chemical Society.

Rees, T.F.; Cleveland, J.M.; Carl, Gottschall W.

1978-01-01

171

Plutonium Chemistry in the UREX+ Separation Processes  

SciTech Connect

The project "Plutonium Chemistry in the UREX+ Separation Processes” is led by Dr. Alena Paulenova of Oregon State University under collaboration with Dr. George Vandegrift of ANL and Dr. Ken Czerwinski of the University of Nevada at Las Vegas. The objective of the project is to examine the chemical speciation of plutonium in UREX+ (uranium/tributylphosphate) extraction processes for advanced fuel technology. Researchers will analyze the change in speciation using existing thermodynamics and kinetic computer codes to examine the speciation of plutonium in aqueous and organic phases. They will examine the different oxidation states of plutonium to find the relative distribution between the aqueous and organic phases under various conditions such as different concentrations of nitric acid, total nitrates, or actinide ions. They will also utilize techniques such as X-ray absorbance spectroscopy and small-angle neutron scattering for determining plutonium and uranium speciation in all separation stages. The project started in April 2005 and is scheduled for completion in March 2008.

ALena Paulenova; George F. Vandegrift, III; Kenneth R. Czerwinski

2009-10-01

172

Materials identification and surveillance project item evaluation. Item: Impure mixture of plutonium oxide and uranium oxide (PUUOXBC05)  

SciTech Connect

In this report Los Alamos researchers characterize properties relevant to storage of an impure mixture of plutonium oxide and uranium oxide (impure mixed oxide (MOX) that is composed of 43.8 mass % plutonium and 17.8 mass % uranium) in accordance with the department of Energy (DOE) standard DOE-STD-3013-96. This is the first sample of an impure mixture of plutonium oxide and uranium oxide to be evaluated by the materials identification and surveillance project. Methods used to characterize the mixture include mass loss-on-calcination measurements, mass loss-on-ignition (LOI) measurements, elemental analysis, plutonium and uranium isotopic analysis, particle analyses measurements, X-ray powder diffraction, thermal desorption mass spectrometry (TDMS), and surface-area analyses. LOI measurements show a steady decrease in magnitude as the calcining temperature is increased. In contrast, calcining at progressively increasing temperatures does not appear to significantly change the specific surface area of the impure MOX. The LOI value for the powder after final 950 C calcination is 0.4 mass %. Water and carbon dioxide are the major gaseous products formed at all temperatures.

Allen, T.; Appert, Q.; Davis, C. [and others

1997-06-01

173

Aqueous methods for recovery of plutonium from pyrochemical residues  

SciTech Connect

Salt residues generated during such pyrochemical processing of plutonium as direct oxide reduction (DOR), electrorefining (ER), and molten salt extraction sometimes contain more plutonium than the economic discard limit, and the plutonium must be recovered. Consequently, the authors have been studying aqueous methods for recovering the plutonium and producing discardable wastes. Most of the work has been the investigation of chloride anion exchange recovery with some interest in leaching and precipitation techniques.

Muscatello, A.C.; Killion, M.E.

1987-01-01

174

EVOLUTION OF CHEMICAL CONDITIONS AND ESTIMATED PLUTONIUM SOLUBILITY IN THE RESIDUAL WASTE LAYER DURING POST-CLOSURE AGING OF TANK 18  

SciTech Connect

This document updates the Eh-pH transitions from grout aging simulations and the plutonium waste release model of Denham (2007, Rev. 1) based on new data. New thermodynamic data for cementitious minerals are used for the grout simulations. Newer thermodynamic data, recommended by plutonium experts (Plutonium Solubility Peer Review Report, LA-UR-12-00079), are used to estimate solubilities of plutonium at various pore water compositions expected during grout aging. In addition, a new grout formula is used in the grout aging simulations and apparent solubilities of coprecipitated plutonium are estimated using data from analysis of Tank 18 residual waste. The conceptual model of waste release and the grout aging simulations are done in a manner similar to that of Denham (2007, Rev. 1). It is assumed that the pore fluid composition passing from the tank grout into the residual waste layer controls the solubility, and hence the waste release concentration of plutonium. Pore volumes of infiltrating fluid of an assumed composition are reacted with a hypothetical grout block using The Geochemist's Workbench{reg_sign} and changes in pore fluid chemistry correspond to the number of pore fluid volumes reacted. As in the earlier document, this results in three states of grout pore fluid composition throughout the simulation period that are termed Reduced Region II, Oxidized Region II, and Oxidized Region III. The one major difference from the earlier document is that pyrite is used to account for reducing capacity of the tank grout rather than pyrrhotite. This poises Eh at -0.47 volts during Reduced Region II. The major transitions in pore fluid composition are shown. Plutonium solubilities are estimated for discrete PuO2(am,hyd) particles and for plutonium coprecipitated with iron phases in the residual waste. Thermodynamic data for plutonium from the Nuclear Energy Agency are used to estimate the solubilities of the discrete particles for the three stages of pore fluid evolution. In Denham (2007, Rev. 1), the solubilities in the oxidized regions were estimated at Eh values in equilibrium with dissolved oxygen. Here, these are considered to be maximum possible solubilities because Eh values are unlikely to be in equilibrium with dissolved oxygen. More realistic Eh values are estimated here and plutonium solubilities calculated at these are considered more realistic. Apparent solubilities of plutonium that coprecipitated with iron phases are estimated from Pu:Fe ratios in Tank 18 residual waste and the solubilities of the host iron phases. The estimated plutonium solubilities are shown. Uncertainties in the grout simulations and plutonium solubility estimates are discussed. The primary uncertainty in the grout simulations is that little is known about the physical state of the grout as it ages. The simulations done here are pertinent to a porous medium, which may or may not be applicable to fractured grout, depending on the degree and nature of the fractures. Other uncertainties that are considered are the assumptions about the reducing capacity imparted by blast furnace slag, the effects of varying dissolved carbon dioxide and oxygen concentrations, and the treatment of silica in the simulations. The primary uncertainty in the estimates of plutonium solubility is that little is known about the exact form of plutonium in the residual waste. Other uncertainties include those inherent in the thermodynamic data, pH variations from those estimated in the grout simulations, the effects of the treatment of silica in the grout simulations, and the effect of varying total dissolved carbonate concentrations. The objective of this document is to update the model for solubility controls on release of plutonium from residual waste in closed F-Area waste tanks. The update is based on new information including a new proposed grout formulation, chemical analysis of Tank 18 samples and more current thermodynamic data for plutonium and grout minerals. In addition, minor changes to the modeling of the grout chemical evolution have been made. It shoul

Denham, M.

2012-02-29

175

Precipitation of plutonium from acidic solutions using magnesium oxide  

SciTech Connect

Magnesium oxide will be used as a neutralizing agent for acidic plutonium-containing solutions. It is expected that as the magnesium oxide dissolves, the pH of the solution will rise, and plutonium will precipitate. The resulting solid will be tested for suitability to storage. The liquid is expected to contain plutonium levels that meet disposal limit requirements.

Jones, S.A.

1994-12-05

176

Gas pressure in sealed sample cans concentrated plutonium nitrate  

Microsoft Academic Search

The objective of this work was to establish as fact that the predominant gas evolved from concentrated plutonium nitrate solutions is oxygen. Four sample cans containing plutonium nitrate at various concentrations were sealed using plug valves equipped with pressure gages. The results obtained showed that the gas evolved from concentrated plutonium nitrate solutions is predominately oxygen. It is believed that

1953-01-01

177

15. VIEW OF THE SAFE GEOMETRY PLUTONIUM METAL STORAGE PALLETS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. VIEW OF THE SAFE GEOMETRY PLUTONIUM METAL STORAGE PALLETS FROM THE INSIDE OF AN INPUT-OUTPUT STATION. INDIVIDUAL CONTAINERS OF PLUTONIUM ARE STORED IN THE WATER-FILLED, DOUBLE-WALLED STAINLESS STEEL TUBES THAT ARE WELDED ONTO THE PALLETS. (12/3/88) - Rocky Flats Plant, Plutonium Recovery Facility, Northwest portion of Rocky Flats Plant, Golden, Jefferson County, CO

178

VIEW OF THE INTERIOR OF THE PLUTONIUM LABORATORY IN BUILDING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF THE INTERIOR OF THE PLUTONIUM LABORATORY IN BUILDING 559. THE LABORATORY WAS USED TO ANALYZE THE PURITY OF PLUTONIUM. PLUTONIUM SAMPLES WERE CONTAINED WITHIN GLOVE BOXES - Rocky Flats Plant, Chemical Analytical Laboratory, North-central section of Plant, Golden, Jefferson County, CO

179

10 CFR 71.88 - Air transport of plutonium.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Air transport of plutonium. 71.88 Section 71.88 Energy...Procedures § 71.88 Air transport of plutonium. (a) Notwithstanding the provisions...applicable, the licensee shall assure that plutonium in any form, whether for...

2014-01-01

180

Calculated Phonon Spectra of Plutonium at High Temperatures  

E-print Network

Calculated Phonon Spectra of Plutonium at High Temperatures X. Dai,1 S. Y. Savrasov,2 * G. Kotliar dynamical proper- ties of plutonium using an electronic structure method, which incorporates correlation anharmonic and can be stabilized at high temperatures by its phonon entropy. Plutonium (Pu) is a material

Savrasov, Sergej Y.

181

Application of Fusion Neutron Source for Denaturing of Plutonium  

Microsoft Academic Search

Potential of DT fusion neutron source to enhance proliferation resistance properties of plutonium by means of its isotopic denaturing is addressed. The approach is exemplified by denaturing of pure Pu and plutonium of typical LWR spent fuel through transmutation of neptunium. The essential feature of a fusion driven system proposed in the study is a zero mass balance of plutonium:

Alan TAKIBAYEV; Masaki SAITO; Hiroshi SAGARA

2007-01-01

182

REVIEW OF PLUTONIUM OXIDATION LITERATURE  

SciTech Connect

A brief review of plutonium oxidation literature was conducted. The purpose of the review was to ascertain the effect of oxidation conditions on oxide morphology to support the design and operation of the PDCF direct metal oxidation (DMO) furnace. The interest in the review was due to a new furnace design that resulted in oxide characteristics that are different than those of the original furnace. Very little of the published literature is directly relevant to the DMO furnace operation, which makes assimilation of the literature data with operating conditions and data a convoluted task. The oxidation behavior can be distilled into three regimes, a low temperature regime (RT to 350 C) with a relatively slow oxidation rate that is influenced by moisture, a moderate temperature regime (350-450 C) that is temperature dependent and relies on more or less conventional oxidation growth of a partially protective oxide scale, and high temperature oxidation (> 500 C) where the metal autocatalytically combusts and oxidizes. The particle sizes obtained from these three regimes vary with the finest being from the lowest temperature. It is surmised that the slow growth rate permits significant stress levels to be achieved that help break up the oxides. The intermediate temperatures result in a fairly compact scale that is partially protective and that grows to critical thickness prior to fracturing. The growth rate in this regime may be parabolic or paralinear, depending on the oxidation time and consequently the oxide thickness. The high temperature oxidation is invariant in quiescent or nearly quiescent conditions due to gas blanketing while it accelerates with temperature under flowing conditions. The oxide morphology will generally consist of fine particles (<15 {micro}m), moderately sized particles (15 < x < 250 {micro}m) and large particles (> 250 {micro}m). The particle size ratio is expected to be < 5%, 25%, and 70% for fine, medium and large particles, respectively, for metal temperatures in the 500-600 C range.

Korinko, P.

2009-11-12

183

Plutonium transport in the environment.  

PubMed

The recent estimated global stockpile of separated plutonium (Pu) worldwide is about 500 t, with equal contributions from nuclear weapons and civilian nuclear energy. Independent of the United States' future nuclear energy policy, the current large and increasing stockpile of Pu needs to be safely isolated from the biosphere and stored for thousands of years. Recent laboratory and field studies have demonstrated the ability of colloids (1-1000 nm particles) to facilitate the migration of strongly sorbing contaminants such as Pu. In understanding the dominant processes that may facilitate the transport of Pu, the initial source chemistry and groundwater chemistry are important factors, as no one process can explain all the different field observations of Pu transport. Very little is known about the molecular-scale geochemical and biochemical mechanisms controlling Pu transport, leaving our conceptual model incomplete. Equally uncertain are the conditions that inhibit the cycling and mobility of Pu in the subsurface. Without a better mechanistic understanding for Pu at the molecular level, we cannot advance our ability to model its transport behavior and achieve confidence in predicting long-term transport. Without a conceptual model that can successfully predict long-term Pu behavior and ultimately isolation from the biosphere, the public will remain skeptical that nuclear energy is a viable and an attractive alternative to counter global warming effects of carbon-based energy alternatives. This review summarizes our current understanding of the relevant conditions and processes controlling the behavior of Pu in the environment, gaps in our scientific knowledge, and future research needs. PMID:23458827

Kersting, Annie B

2013-04-01

184

Method for dissolving delta-phase plutonium  

DOEpatents

A process for dissolving plutonium, and in particular, delta-phase plutonium. The process includes heating a mixture of nitric acid, hydroxylammonium nitrate (HAN) and potassium fluoride to a temperature between 40.degree. and 70.degree. C., then immersing the metal in the mixture. Preferably, the nitric acid has a concentration of not more than 2M, the HAN approximately 0.66M, and the potassium fluoride 0.1M. Additionally, a small amount of sulfamic acid, such as 0.1M can be added to assure stability of the HAN in the presence of nitric acid. The oxide layer that forms on plutonium metal may be removed with a non-oxidizing acid as a pre-treatment step.

Karraker, David G. (1600 Sherwood Pl., SE., Aiken, SC 29801)

1992-01-01

185

The United States Plutonium Balance, 1944 - 2009  

SciTech Connect

This report updates the report -Plutonium: The first 50 years- which was released by the U.S.Department of Energy (DOE) in 1996. The topic of both reports is plutonium, sometimes referred to as Pu-239, which is capable of sustaining a nuclear chain reaction and is used in nuclear weapons and for nuclear power production. This report updates 1994 data through 2009. The four most significant changes since 1994 include: (a) the completion of cleanup activities at the Rocky Flats Plant in 2005; (b) material consolidation and disposition activities, especially shipments from Hanford to the Savannah River Site; (c) the 2007 declaration of an additional 9.0 MT of weapons grade plutonium to be surplus to defense needs in the coming decades; and (d) the opening of the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico in 1999.

none,

2012-06-01

186

Excess plutonium disposition: The deep borehole option  

SciTech Connect

This report reviews the current status of technologies required for the disposition of plutonium in Very Deep Holes (VDH). It is in response to a recent National Academy of Sciences (NAS) report which addressed the management of excess weapons plutonium and recommended three approaches to the ultimate disposition of excess plutonium: (1) fabrication and use as a fuel in existing or modified reactors in a once-through cycle, (2) vitrification with high-level radioactive waste for repository disposition, (3) burial in deep boreholes. As indicated in the NAS report, substantial effort would be required to address the broad range of issues related to deep bore-hole emplacement. Subjects reviewed in this report include geology and hydrology, design and engineering, safety and licensing, policy decisions that can impact the viability of the concept, and applicable international programs. Key technical areas that would require attention should decisions be made to further develop the borehole emplacement option are identified.

Ferguson, K.L.

1994-08-09

187

Computerized plutonium wound-analysis system  

SciTech Connect

A new plutonium wound monitor has been developed at Los Alamos to upgrade a system which has been in use for about five years. The instrument, called a Computerized Wound Screening System, is designed around a readily available personal computer. It includes a full-function 256-channel pulse height analyzer and software necessary to calculate plutonium and americium activity from a spectrum. This new system provides medical and health physics personnel with considerable flexability in recognizing and recording situations where a wound incurred in a plutonium processing facility might be contaminated. This flexibility includes fast, accurate determination of contaminants in a wound, hard copy printout of results, and full patient logging capabilities via flexible disk storage. Use of a low cost computer greatly simplifies hardware and software design, and makes duplication of the instrument very simple and inexpensive.

Waechter, D.A.; Brake, R.J.; Vasilik, D.G.; Erkkila, B.H.

1983-01-01

188

ESTIMATING IMPURITIES IN SURPLUS PLUTONIUM FOR DISPOSITION  

SciTech Connect

The United States holds at least 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition of the National Nuclear Security Administration and the DOE Office of Environmental Management. Many of the items that require disposition are only partially characterized, and SRNL uses a variety of techniques to predict the isotopic and chemical properties that are important for processing through the Mixed Oxide Fuel Fabrication Facility and alternative disposition paths. Recent advances in laboratory tools, including Prompt Gamma Analysis and Peroxide Fusion treatment, provide data on the existing inventories that will enable disposition without additional, costly sampling and destructive analysis.

Allender, J.; Moore, E.

2013-07-17

189

Disposition of plutonium in deep boreholes  

SciTech Connect

Substantial inventories of excess plutonium are expected to result from dismantlement of U.S. and Russian nuclear weapons. Disposition of this material should be a high priority in both countries. A variety of disposition options are under consideration. One option is to place the plutonium either directly or in an immobilized form at the bottom of a deep borehole that is then sealed. Deep-borehole disposition involves placing plutonium several kilometers deep into old, stable, rock formations that have negligible free water present. Containment assurance is based on the presence of ancient groundwater indicating lack of migration and communication with the biosphere. Recovery would be extremely difficult (costly) and impossible to accomplish clandestinely.

Halsey, W.G.; Jardine, L.J.; Walter, C.E.

1995-05-01

190

Alternating layers of plutonium and lead or indium as surrogate for plutonium  

SciTech Connect

Elemental plutonium (Pu) assumes more crystal structures than other elements, plausibly due to bonding f electrons becoming non-bonding. Complex geometries hamper understanding of the transition in Pu, but calculations predict this transition in a system with simpler geometry: alternating layers either of plutonium and lead or of plutonium and indium. Here the transition occurs via a pairing-up of atoms within Pu layers. Calculations stepping through this pairing-up reveal valuable details of the transition, for example that the transition from bonding to non-bonding proceeds smoothly.

Rudin, Sven Peter [Los Alamos National Laboratory

2009-01-01

191

Economic discard limits for plutonium recovery  

SciTech Connect

Purpose of the audit was to determine whether the Department used economic discard limits (EDL) for the recovery of weapons-grade plutonium and whether the EDL calculations, if used, were current and accurate. Our review showed that EDL limits had not always been used or were not accurately calculated by some management and operating (M and O) contractors. This occurred because Department management had not updated or ensured implementation of EDL policy and procedures. Partial application of current EDL policy at two contractors prevented the unnecessary disposal of over $5.5 million in plutonium.

Not Available

1988-02-11

192

Dehydration of plutonium or neptunium trichloride hydrate  

DOEpatents

A process is described for preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride.

Foropoulos, J. Jr.; Avens, L.R.; Trujillo, E.A.

1992-03-24

193

Dehydration of plutonium or neptunium trichloride hydrate  

DOEpatents

A process of preparing anhydrous actinide metal trichlorides of plutonium or neptunium by reacting an aqueous solution of an actinide metal trichloride selected from the group consisting of plutonium trichloride or neptunium trichloride with a reducing agent capable of converting the actinide metal from an oxidation state of +4 to +3 in a resultant solution, evaporating essentially all the solvent from the resultant solution to yield an actinide trichloride hydrate material, dehydrating the actinide trichloride hydrate material by heating the material in admixture with excess thionyl chloride, and recovering anhydrous actinide trichloride is provided.

Foropoulos, Jr., Jerry (Los Alamos, NM); Avens, Larry R. (Los Alamos, NM); Trujillo, Eddie A. (Espanola, NM)

1992-01-01

194

Solubility of plutonium from rumen contents of cattle grazing on plutonium- contaminated desert vegetation in in vitro bovine gastrointestinal fluids  

Microsoft Academic Search

Rumen contents of cattle grazing on plutonium-contaminated desert ; vegetation at the Nevada Test Site were incubated in simulated bovine ; gastrointestinal fluids to study the alimentary solubility of plutonium. Trials ; were run during November 1973, and during February, May, July and August 1974. ; During the May and July trials, a large increase in plutonium solubility ; accompanied

J. Barth; M. G. White; P. B. Dunaway

1975-01-01

195

Materials identification and surveillance project item evaluation: Items, impure plutonium oxide (ATL27960) and pure plutonium oxide (PEOR3258)  

Microsoft Academic Search

In this report, Los Alamos scientists characterize properties relevant to storage of an impure plutonium oxide (74 mass % plutonium) in accordance with the Department of Energy (DOE) standard DOE-STD-3013-96. This oxide is of interest because it is the first impure plutonium oxide sample to be evaluated and it is similar to other materials that must be stored. Methods used

T. Allen; Q. Appert; C. Davis

1997-01-01

196

Carbon Dioxide Exercise  

NSDL National Science Digital Library

In this activity, students work in groups, plotting carbon dioxide concentrations over time on overheads and estimating the rate of change over five years. Stacked together, the overheads for the whole class show an increase on carbon dioxide over five years and annual variation driven by photosynthesis. This exercise enables students to practice basic quantitative skills and understand how important sampling intervals can be when studying changes over time. A goal is to see how small sample size may give incomplete picture of data.

Randy Richardson

197

Plutonium dispersal in fires: Summary of what is known  

SciTech Connect

In view of the great public apprehension about plutonium and nuclear weapons we should explore ways to prevent, limit, or mitigate possible plutonium dispersals. This review is primarily a tutorial on what is known about plutonium dispersal in fires. It concludes that in most types of fires involving plutonium the amount released will not be an immediate danger to life. Indeed, in many cases very few personnel will receive more than the lung burden allowed by current regulations for plutonium workers. However, the dangers may be significant in special situations, unusual terrains, certain meteorological conditions, and very high burn temperatures.

Condit, R.H.

1993-07-01

198

Weapons-grade plutonium dispositioning. Volume 2: Comparison of plutonium disposition options  

SciTech Connect

The Secretary of Energy requested the National Academy of Sciences (NAS) Committee on International Security and Arms Control to evaluate disposition options for weapons-grade plutonium. The Idaho National Engineering Laboratory (INEL) offered to assist the NAS in this evaluation by investigating the technical aspects of the disposition options and their capability for achieving plutonium annihilation levels greater than 90%. This report was prepared for the NAS to document the gathered information and results from the requested option evaluations. Evaluations were performed for 12 plutonium disposition options involving five reactor and one accelerator-based systems. Each option was evaluated in four technical areas: (1) fuel status, (2) reactor or accelerator-based system status, (3) waste-processing status, and (4) waste disposal status. Based on these evaluations, each concept was rated on its operational capability and time to deployment. A third rating category of option costs could not be performed because of the unavailability of adequate information from the concept sponsors. The four options achieving the highest rating, in alphabetical order, are the Advanced Light Water Reactor with plutonium-based ternary fuel, the Advanced Liquid Metal Reactor with plutonium-based fuel, the Advanced Liquid Metal Reactor with uranium-plutonium-based fuel, and the Modular High Temperature Gas-Cooled Reactor with plutonium-based fuel. Of these four options, the Advanced Light Water Reactor and the Modular High Temperature Gas-Cooled Reactor do not propose reprocessing of their irradiated fuel. Time constraints and lack of detailed information did not allow for any further ratings among these four options. The INEL recommends these four options be investigated further to determine the optimum reactor design for plutonium disposition.

Brownson, D.A.; Hanson, D.J.; Blackman, H.S. [and others

1993-06-01

199

Fifty years of plutonium exposure to the Mahattan Project plutonium workers: An update  

Microsoft Academic Search

Twenty-six white male workers who did the original plutonium research and development work at Los Alamos have been examined periodically over the past 50 y to identify possible health effects from internal plutonium depositions. Their effective doses range from 0.1 to 7.2 Sv with a median value of 1.25 Sv. As of the end of 1994, 7 individuals have died

George L. Voelz; James N. P. Lawrence; Emily R. Johnson

1997-01-01

200

PERSONAL MONITOR FOR NITROGEN DIOXIDE  

EPA Science Inventory

An attempt was made to develop a personal monitor to measure nitrogen dioxide. Sampling of nitrogen dioxide is accomplished by permeation through a silicone membrane into a alkaline thymol blue solution. The nitrogen dioxide is converted to nitrite and is then quantitated by colo...

201

Arnold Schwarzenegger THE CARBON DIOXIDE  

E-print Network

i Arnold Schwarzenegger Governor THE CARBON DIOXIDE ABATEMENT POTENTIAL OF CALIFORNIA'S MID, Afzal Siddiqui, and Judy Lai. 2011. The Carbon Dioxide Abatement Potential of California's Mid/Agricultural/Water EndUse Energy Efficiency · Renewable Energy Technologies · Transportation The Carbon Dioxide

202

8, 73157337, 2008 Carbon dioxide  

E-print Network

ACPD 8, 7315­7337, 2008 Carbon dioxide distributions over Europe C. Gurk et al. Title Page Abstract distributions of carbon dioxide over Europe C. Gurk1 , H. Fischer1 , P. Hoor1 , M.G. Lawrence1 , J. Lelieveld1 Publications on behalf of the European Geosciences Union. 7315 #12;ACPD 8, 7315­7337, 2008 Carbon dioxide

Paris-Sud XI, Université de

203

Plutonium Immobilization Can Loading Equipment Review  

SciTech Connect

This report lists the operations required to complete the Can Loading steps on the Pu Immobilization Plant Flow Sheets and evaluates the equipment options to complete each operation. This report recommends the most appropriate equipment to support Plutonium Immobilization Can Loading operations.

Kriikku, E. [Westinghouse Savannah River Company, AIKEN, SC (United States); Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.

1998-05-01

204

233-S plutonium concentration facility hazards assessment  

SciTech Connect

This document establishes the technical basis in support of Emergency Planning activities for the 233-S Plutonium Concentration Facility on the Hanford Site. The document represents an acceptable interpretation of the implementing guidance document for DOE ORDER 5500.3A. Through this document, the technical basis for the development of facility specific Emergency Action Levels and the Emergency Planning Zone is demonstrated.

Broz, R.E.

1994-12-19

205

Predicted transport properties of liquid plutonium  

Microsoft Academic Search

The fluid-phase transport properties, diffusivity and viscosity, are calculated by equilibrium and nonequilibrium techniques for plutonium, whose interatomic interactions are described by the modified embedded-atom method. The transport coefficients are evaluated at zero pressure, for temperatures between 950 K and 1300 K. We find the calculated viscosity to be noticeably higher than experiment, while the structure of liquid Pu appears

F. J. Cherne; M. I. Baskes; B. L. Holian

2003-01-01

206

Plutonium isotope ratio variations in North America  

SciTech Connect

Historically, approximately 12,000 TBq of plutonium was distributed throughout the global biosphere by thermo nuclear weapons testing. The resultant global plutonium fallout is a complex mixture whose {sup 240}Pu/{sup 239}Pu atom ratio is a function of the design and yield of the devices tested. The average {sup 240}Pu/{sup 239}Pu atom ratio in global fallout is 0.176 + 014. However, the {sup 240}Pu/{sup 239}Pu atom ratio at any location may differ significantly from 0.176. Plutonium has also been released by discharges and accidents associated with the commercial and weapons related nuclear industries. At many locations contributions from this plutonium significantly alters the {sup 240}Pu/{sup 239}Pu atom ratios from those observed in global fallout. We have measured the {sup 240}Pu/{sup 239}Pu atom ratios in environmental samples collected from many locations in North America. This presentation will summarize the analytical results from these measurements. Special emphasis will be placed on interpretation of the significance of the {sup 240}Pu/{sup 239}Pu atom ratios measured in environmental samples collected in the Arctic and in the western portions of the United States.

Steiner, Robert E [Los Alamos National Laboratory; La Mont, Stephen P [Los Alamos National Laboratory; Eisele, William F [Los Alamos National Laboratory; Fresquez, Philip R [Los Alamos National Laboratory; Mc Naughton, Michael [Los Alamos National Laboratory; Whicker, Jeffrey J [Los Alamos National Laboratory

2010-12-14

207

Proliferation Resistance Attributes of Advanced Plutonium Processing  

Microsoft Academic Search

To obtain public acceptance for future use of Pu, new concepts must overcome the present concerns about environmental compliance as well as con- cerns about misusing plutonium of the civil nuclear fuel cycle for nuclear explosives e.g. by terrorists. In future the preferable remedy is the multi-recycling of all transuranium elements in fast neutron reac- tors. In such a partitioning

L. Koch

208

NNSS Soils Monitoring: Plutonium Valley (CAU366)  

SciTech Connect

The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Nevada Site Office (NSO), Environmental Restoration Soils Activity has authorized the Desert Research Institute (DRI) to conduct field assessments of potential sediment transport of contaminated soil from Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites Contamination Area (CA) during precipitation runoff events.

Miller, Julianne J.; Mizell, Steve A.; Nikolich, George; Campbell, Scott

2012-02-01

209

High temperature vapor pressure of pure plutonium  

Microsoft Academic Search

High temperature vapor pressure measurements have been made on pure plutonium metal by the Knudsen effusion technique. The reported experimental results extend into the transition region between molecular and viscous or hydrodynamic flow. Under the conditions used, linearity was observed up to temperatures in excess of 2200 K where pressures approaching 100 Pa were measured. The results over the temperature

M. H. Bradbury; R. W. Ohse

1979-01-01

210

Preparation of Plutonium Hexafluoride. Recovery of Plutonium from Waste Dross; PREPARATION DE L'HEXAFLUORURE DE PLUTONIUM. RECUPERATION DU PLUTONIUM DES SCORIES D'ELABORATION  

Microsoft Academic Search

The influence of various physical factors on the rate of fluorination of ; solid plutonium tetrafluoride by fluorine was studied. In a horizontal oven with ; a circulation for pure fluorine at atmospheric pressure and 520#DEC, at a ; fluorine rate of 9 liters\\/hour, it is possible to transform 3 gm of tetrafluoride ; to hexafluoride with about 100% transformation

Gendre

1962-01-01

211

Analysis of femtogram-sized plutonium samples  

SciTech Connect

This report describes a study to determine how well isotopic ratios can be measured for very small samples of plutonium. Resin beads were used to simulate particles; for samples ranging from 5--16 fg, collection efficiencies (ions collected per atom loaded) of 4--9% were obtained. Isotopic ratios with 4% precision and accuracy (240/239) were obtained.

Smith, D.H.; McKown, H.S.; Bostick, D.T.; Coleman, R.M.; Duckworth, D.C.; McPherson, R.L.

1994-01-01

212

PLUTONIUM SPECIATION, SOLUBILIZATION, AND MIGRATION IN SOILS  

EPA Science Inventory

The DOE is currently conducting cleanup activities at its nuclear weapons development sites, many of which have accumulated plutonium (Pu) in soils for 50 years. There is scientific uncertainty about the levels of risk to human health posed by this accumulation and whether Pu is ...

213

Plutonium Immobilization Can Loading Preliminary Specifications  

SciTech Connect

This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.

Kriikku, E.

1998-11-25

214

Electrochemically Modulated Separation for Plutonium Safeguards  

SciTech Connect

Accurate and timely analysis of plutonium in spent nuclear fuel is critical in nuclear safeguards for detection of both protracted and rapid plutonium diversions. Gamma spectroscopy is a viable method for accurate and timely measurements of plutonium provided that the plutonium is well separated from the interfering fission and activation products present in spent nuclear fuel. Electrochemically modulated separation (EMS) is a method that has been used successfully to isolate picogram amounts of Pu from nitric acid matrices. With EMS, Pu adsorption may be turned "on" and "off" depending on the applied voltage, allowing for collection and stripping of Pu without the addition of chemical reagents. In this work, we have scaled up the EMS process to isolate microgram quantities of Pu from matrices encountered in spent nuclear fuel during reprocessing. Several challenges have been addressed including surface area limitations, radiolysis effects, electrochemical cell performance stability, and chemical interferences. After these challenges were resolved, 6 µg Pu was deposited in the electrochemical cell with approximately an 800-fold reduction of fission and activation product levels from a spent nuclear fuel sample. Modeling showed that these levels of Pu collection and interference reduction may not be sufficient for Pu detection by gamma spectroscopy. The main remaining challenges are to achieve a more complete Pu isolation and to deposit larger quantities of Pu for successful gamma analysis of Pu. If gamma analyses of Pu are successful, EMS will allow for accurate and timely on-site analysis for enhanced Pu safeguards.

Pratt, Sandra H.; Breshears, Andrew T.; Arrigo, Leah M.; Schwantes, Jon M.; Duckworth, Douglas C.

2013-12-31

215

Chlorine Dioxide (Gas)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Chlorine dioxide (ClO2) gas is registered by the U.S. Environmental Protection Agency (EPA) as a sterilant for use in manufacturing, laboratory equipment, medical devices, environmental surfaces, tools and clean rooms. Aqueous ClO2 is registered by the EPA as a surface disinfectant and sanitizer fo...

216

Investigating Nitrogen Dioxide  

NSDL National Science Digital Library

Students will investigate Nitrogen Dioxide levels in the atmosphere during a one year time span using data sets from MyNASAData website. They will draw conclusions about what factors around the world effect NO2 levels (season, population, industry, etc.)

217

Carbon dioxide recycling  

EPA Science Inventory

The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the ?Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

218

Atmospheric Carbon Dioxide  

NSDL National Science Digital Library

This figure, the famous Keeling Curve, shows the history of atmospheric carbon dioxide concentrations as directly measured at Mauna Loa, Hawaii. This curve is an essential piece of evidence that shows the increased greenhouse gases that cause recent increases in global temperatures.

Robert A. Rohde

219

Carbon dioxide sensor  

SciTech Connect

The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

Dutta, Prabir K. (Worthington, OH); Lee, Inhee (Columbus, OH); Akbar, Sheikh A. (Hilliard, OH)

2011-11-15

220

Carbon Dioxide Increases  

NSDL National Science Digital Library

In this problem set, learners will analyze the Keeling Curve showing carbon dioxide concentration in the atmosphere since 1985 to answer a series of questions. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

221

Sulfur Dioxide Pollution Monitor.  

ERIC Educational Resources Information Center

The sulfur dioxide pollution monitor described in this document is a government-owed invention that is available for licensing. The background of the invention is outlined, and drawings of the monitor together with a detailed description of its function are provided. A sample stream of air, smokestack gas or the like is flowed through a…

National Bureau of Standards (DOC), Washington, DC.

222

In search of plutonium: A nonproliferation journey  

NASA Astrophysics Data System (ADS)

In February 1992, I landed in the formerly secret city of Sarov, the Russian Los Alamos, followed a few days later by a visit to Snezhinsk, their Livermore. The briefings we received of the Russian nuclear weapons program and tours of their plutonium, reactor, explosives, and laser facilities were mind boggling considering the Soviet Union was dissolved only two months earlier. This visit began a 17-year, 41 journey relationship with the Russian nuclear complex dedicated to working with them in partnership to protect and safeguard their weapons and fissile materials, while addressing the plight of their scientists and engineers. In the process, we solved a forty-year disagreement about the plutonium-gallium phase diagram and began a series of fundamental plutonium science workshops that are now in their tenth year. At the Yonbyon reprocessing facility in January 2004, my North Korean hosts had hoped to convince me that they have a nuclear deterrent. When I expressed skepticism, they asked if I wanted to see their ``product.'' I asked if they meant the plutonium; they replied, ``Well, yes.'' Thus, I wound up holding 200 grams of North Korean plutonium (in a sealed glass jar) to make sure it was heavy and warm. So began the first of my six journeys to North Korea to provide technical input to the continuing North Korean nuclear puzzle. In Trombay and Kalpakkam a few years later I visited the Indian nuclear research centers to try to understand how India's ambitious plans for nuclear power expansion can be accomplished safely and securely. I will describe these and other attempts to deal with the nonproliferation legacy of the cold war and the new challenges ahead. )

Hecker, Siegfried

2010-02-01

223

Carbon dioxide dangers demonstration model  

USGS Publications Warehouse

Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

Venezky, Dina; Wessells, Stephen

2010-01-01

224

Gas-phase energetics of actinide oxides: an assessment of neutral and cationic monoxides and dioxides from thorium to curium.  

PubMed

An assessment of the gas-phase energetics of neutral and singly and doubly charged cationic actinide monoxides and dioxides of thorium, protactinium, uranium, neptunium, plutonium, americium, and curium is presented. A consistent set of metal-oxygen bond dissociation enthalpies, ionization energies, and enthalpies of formation, including new or revised values, is proposed, mainly based on recent experimental data and on correlations with the electronic energetics of the atoms or cations and with condensed-phase thermochemistry. PMID:19725530

Marçalo, Joaquim; Gibson, John K

2009-11-12

225

Gas-Phase Energetics of Actinide Oxides: An Assessment of Neutral and Cationic Monoxides and Dioxides from Thorium to Curium  

NASA Astrophysics Data System (ADS)

An assessment of the gas-phase energetics of neutral and singly and doubly charged cationic actinide monoxides and dioxides of thorium, protactinium, uranium, neptunium, plutonium, americium, and curium is presented. A consistent set of metal-oxygen bond dissociation enthalpies, ionization energies, and enthalpies of formation, including new or revised values, is proposed, mainly based on recent experimental data and on correlations with the electronic energetics of the atoms or cations and with condensed-phase thermochemistry.

Marçalo, Joaquim; Gibson, John K.

2009-09-01

226

Gas-phase energies of actinide oxides -- an assessment of neutral and cationic monoxides and dioxides from thorium to curium  

SciTech Connect

An assessment of the gas-phase energetics of neutral and singly and doubly charged cationic actinide monoxides and dioxides of thorium, protactinium, uranium, neptunium, plutonium, americium, and curium is presented. A consistent set of metal-oxygen bond dissociation enthalpies, ionization energies, and enthalpies of formation, including new or revised values, is proposed, mainly based on recent experimental data and on correlations with the electronic energetics of the atoms or cations and with condensed-phase thermochemistry.

Marcalo, Joaquim; Gibson, John K.

2009-08-10

227

Plutonium, Mineralogy and Radiation Effects  

NASA Astrophysics Data System (ADS)

During the past fifty years, more than 1,800 metric tonnes of Pu and substantial quantities of other "minor" actinides, such as Np, Am and Cm, have been generated in nuclear reactors. Some of these transuranic elements can be a source of energy in fission reactions (e.g., 239Pu), a source of fissile material for nuclear weapons (e.g., 239Pu and 237Np), or are of environmental concern because of their long half- lives and radiotoxicity (e.g., 239Pu, t1/2 = 24,100 years, and 237Np, t1/2 = 2.1 million years). There are two basic strategies for the disposition of these elements: 1.) to "burn" or transmute the actinides using nuclear reactors or accelerators; 2.) to "sequester" the actinides in chemically durable, radiation-resistant materials that are suitable for geologic disposal. There has been substantial interest in the use of actinide-bearing minerals, such as zircon or isometric pyrochlore, A2B2O7 (A = rare earths; B = Ti, Zr, Sn, Hf; Fd3m; Z=8), for the immobilization of actinides, particularly plutonium. One of the principal concerns has been the accumulation of structural damage caused by alpha-decay events, particularly from the recoil nucleus. Systematic ion beam irradiation studies of rare-earth pyrochlores have led to the discovery that certain compositions (B = Zr, Hf) are stable to very high fluences of alpha-decay event damage. Some compositions, Gd2Ti2O7, are amorphized at relatively low doses (0.2 displacements per atom, dpa, at room temperature), while other compositions, Gd2Zr2O7, do not amorphize (even at doses of > 40 dpa at 25K), but instead disorder to a defect fluorite structure. By changing the composition of the A-site (e.g., substitution of different rare earth elements), the temperature above which the pyrochlore composition can no longer be amorphized, Tc, varies by >600 K (e.g., Lu2Ti2O7: Tc = 480 K; Gd2Ti2O7: Tc = 1120 K). The variation in response to irradiation as a function of composition can be used to model the long-term accumulation of radiation damage as a function of the thermal period of a geologic repository. As an example, with a 10 wt.% loading of 239Pu, Gd2Ti2O7 will become amorphous in less than 1,000 years, while Gd2Zr2O7 will persist as a disordered defect fluorite structure. Thus, the radiation stability of different pyrochlores is closely related to the structural distortions that occur for specific pyrochlore compositions and the electronic structure of the B-site cation. This understanding provides the basis for designing materials for the safe, long-term immobilization and sequestration of actinides.

Ewing, R. C.

2006-05-01

228

A Note on the Reaction of Hydrogen and Plutonium  

SciTech Connect

Plutonium hydride has many practical and experimental purposes. The reaction of plutonium and hydrogen has interesting characteristics, which will be explored in the following analysis. Plutonium is a radioactive actinide metal that emits alpha particles. When plutonium metal is exposed to air, the plutonium oxides and hydrides, and the volume increases. PuH{sub 2} and Pu{sub 2}O{sub 3} are the products. Hydrogen is a catalyst for plutonium's corrosion in air. The reaction can take place at room temperature because it is fairly insensitive to temperature. Plutonium hydride, or PuH{sub 2}, is black and metallic. After PuH{sub 2} is formed, it quickly flakes off and burns. The reaction of hydrogen and plutonium is described as pyrophoric because the product will spontaneously ignite when oxygen is present. This tendency must be considered in the storage of metal plutonium. The reaction is characterized as reversible and nonstoichiometric. The reaction goes as such: Pu + H{sub 2} {yields} PuH{sub 2}. When PuH{sub 2} is formed, the hydrogen/plutonium ratio is between 2 and 2.75 (approximately). As more hydrogen is added to the system, the ratio increases. When the ratio exceeds 2.75, PuH{sub 3} begins to form along with PuH{sub 2}. Once the ratio surpasses 2.9, only PuH{sub 3} remains. The volume of the plutonium sample increases because of the added hydrogen and the change in crystal structure which the sample undergoes. As more hydrogen is added to a system of metal plutonium, the crystal structure evolves. Plutonium has a crystal structure classified as monoclinic. A monoclinic crystal structure appears to be a rectangular prism. When plutonium reacts with hydrogen, the product PuH{sub 2}, becomes a fluorite structure. It can also be described as a face centered cubic structure. PuH{sub 3} forms a hexagonal crystal structure. As plutonium evolves from metal plutonium to plutonium hydride to plutonium trihydride, the crystal structure evolves from monoclinic to fluorite to hexagonal. This change in crystal structure as a result of adding hydrogen is a shared characteristic with other actinide elements. Americium is isostructural with plutonium because they both form cubic dihyrides and hexagonal trihydrides. Reacting hydrogen with plutonium has the practical application of separating plutonium from other materials that don't react as well with hydrogen. When plutonium is placed in a chamber where there is very little oxygen, it can react with hydrogen without igniting. The hydrogen plutonium reaction can then be reversed, thus regaining the separated plutonium. Another application of this reaction is that it can be used to predict how plutonium reacts with other substances. Deuterium and tritium are two isotopes of hydrogen that are of interest. They are known to react likewise to hydrogen because they have similar properties. The reaction of plutonium and isotopes of hydrogen can prove to be very informative.

Noone, Bailey C [Los Alamos National Laboratory

2012-08-15

229

PLUTONIUM CONTAMINATION VALENCE STATE DETERMINATION USING X-RAY ABSORPTION FINE STRUCTURE PERMITS CONCRETE RECYCLE  

SciTech Connect

This paper describes the determination of the speciation of plutonium contamination present on concrete surfaces at the Rocky Flats Environmental Technology Site (RFETS). At RFETS, the plutonium processing facilities have been contaminated during multiple events over their 50 year operating history. Contamination has resulted from plutonium fire smoke, plutonium fire fighting water, milling and lathe operation aerosols, furnace operations vapors and plutonium ''dust'' diffusion.

Ervin, P. F.; Conradson, S. D.

2002-02-25

230

Carbon Dioxide Landscape  

NASA Technical Reports Server (NTRS)

23 July 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of some of the widely-varied terrain of the martian south polar residual cap. The landforms here are composed mainly of frozen carbon dioxide. Each year since MGS arrived in 1997, the scarps that bound each butte and mesa, or line the edges of each pit, in the south polar region, have changed a little bit as carbon dioxide is sublimed away. The scarps retreat at a rate of about 3 meters (3 yards) per martian year. Most of the change occurs during each southern summer.

Location near: 86.7oS, 9.8oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

2005-01-01

231

CARBON DIOXIDE FIXATION.  

SciTech Connect

Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

FUJITA,E.

2000-01-12

232

Titanium dioxide photocatalysis  

Microsoft Academic Search

Scientific studies on photocatalysis started about two and a half decades ago. Titanium dioxide (TiO2), which is one of the most basic materials in our daily life, has emerged as an excellent photocatalyst material for environmental purification. In this review, current progress in the area of TiO2 photocatalysis, mainly photocatalytic air purification, sterilization and cancer therapy are discussed together with

Akira Fujishima; Tata N. Rao; Donald A. Tryk

2000-01-01

233

Frozen Carbon Dioxide  

NASA Technical Reports Server (NTRS)

1 August 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a south polar residual cap landscape, formed in frozen carbon dioxide. There is no place on Earth that one can go to visit a landscape covering thousands of square kilometers with frozen carbon dioxide, so mesas, pits, and other landforms of the martian south polar region are as alien as they are beautiful. The scarps of the south polar region are known from thousands of other MGS MOC images to retreat at a rate of about 3 meters (3 yards) per martian year, indiating that slowly, over the course of the MGS mission, the amount of carbon dioxide in the martian atmosphere has probably been increasing.

Location near: 86.9oS, 25.5oW Image width: width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Spring

2005-01-01

234

Carbon Dioxide Landforms  

NASA Technical Reports Server (NTRS)

19 March 2004 The martian south polar residual ice cap is mostly made of frozen carbon dioxide. There is no place on Earth that a person can go to see the landforms that would be produced by erosion and sublimation of hundreds or thousands of cubic kilometers of carbon dioxide. Thus, the south polar cap of Mars is as alien as alien can get. This image, acquired in February 2004 by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC), shows how the cap appears in summer as carbon dioxide is subliming away, creating a wild pattern of pits, mesas, and buttes. Darker surfaces may be areas where the ice contains impurities, such as dust, or where the surface has been roughened by the removal of ice. This image is located near 86.3oS, 0.8oW. This picture covers an area about 3 km (1.9 mi) across. Sunlight illuminates the scene from the top/upper left.

2004-01-01

235

Chlorine dioxide and hemodialysis  

SciTech Connect

Because it has little or no tendency to generate carcinogenic trihalomethanes such as chloroform, chlorine dioxide is an attractive alternative to chlorine for drinking water disinfection. There are, however, concerns about its acute toxicity, and the toxic effects of its by-products, chlorite and chlorate. The human experience with chlorine dioxide in both controlled, prospective studies and in actual use situations in community water supplies have as yet failed to reveal adverse health effects. The EPA has recommended standards of 0.06 mg/L for chlorine dioxide and standards of 0.007 mg/L for chlorite and chlorate in drinking water. Among groups who may be at special risk from oxychlorines in drinking water are patients who must undergro chronic extracorporeal hemodialysis. Although even units for home hemodialysis are supposed to be equipped with devices which effectively remove oxychlorines, there is a always a possibility of operator error or equipment failure. When the equipment is adequately maintained, it is likely that dialysis patients will have more intensive exposures from drinking water than from dialysis fluids despite the much larger volumes of water that are involved in dialysis. This paper discusses a hemodialysis and the standards and effects of oxychlorines. 90 refs., 2 tabs.

Smith, R.P. (Dartmouth Coll., Hanover, NH (USA). Dept. of Pharmacology and Toxicology)

1989-05-01

236

10 CFR 140.13a - Amount of financial protection required for plutonium processing and fuel fabrication plants.  

Code of Federal Regulations, 2014 CFR

...Amount of financial protection required for plutonium processing and fuel fabrication plants...Amount of financial protection required for plutonium processing and fuel fabrication plants...70 of this chapter to possess and use plutonium at a plutonium processing and...

2014-01-01

237

10 CFR 140.13a - Amount of financial protection required for plutonium processing and fuel fabrication plants.  

Code of Federal Regulations, 2012 CFR

...Amount of financial protection required for plutonium processing and fuel fabrication plants...Amount of financial protection required for plutonium processing and fuel fabrication plants...70 of this chapter to possess and use plutonium at a plutonium processing and...

2012-01-01

238

10 CFR 140.13a - Amount of financial protection required for plutonium processing and fuel fabrication plants.  

Code of Federal Regulations, 2013 CFR

...Amount of financial protection required for plutonium processing and fuel fabrication plants...Amount of financial protection required for plutonium processing and fuel fabrication plants...70 of this chapter to possess and use plutonium at a plutonium processing and...

2013-01-01

239

10 CFR 140.13a - Amount of financial protection required for plutonium processing and fuel fabrication plants.  

Code of Federal Regulations, 2011 CFR

...Amount of financial protection required for plutonium processing and fuel fabrication plants...Amount of financial protection required for plutonium processing and fuel fabrication plants...70 of this chapter to possess and use plutonium at a plutonium processing and...

2011-01-01

240

10 CFR 140.13a - Amount of financial protection required for plutonium processing and fuel fabrication plants.  

Code of Federal Regulations, 2010 CFR

...Amount of financial protection required for plutonium processing and fuel fabrication plants...Amount of financial protection required for plutonium processing and fuel fabrication plants...70 of this chapter to possess and use plutonium at a plutonium processing and...

2010-01-01

241

Plutonium disposition via immobilization in ceramic or glass  

SciTech Connect

The management of surplus weapons plutonium is an important and urgent task with profound environmental, national, and international security implications. In the aftermath of the Cold War, Presidential Policy Directive 13, and various analyses by renown scientific, technical, and international policy organizations have brought about a focused effort within the Department of Energy to identify and implement paths for the long term disposition of surplus weapons- usable plutonium. The central goal of this effort is to render surplus weapons plutonium as inaccessible and unattractive for reuse in nuclear weapons as the much larger and growing stock of plutonium contained in spent fuel from civilian reactors. One disposition option being considered for surplus plutonium is immobilization, in which the plutonium would be incorporated into a glass or ceramic material that would ultimately be entombed permanently in a geologic repository for high-level waste.

Gray, L.W.; Kan, T.; Shaw, H.F.; Armantrout, A.

1997-03-05

242

Plutonium fractionation in southern Baltic Sea sediments.  

PubMed

In this study, different chemical plutonium fractions (dissolved in water, connected to carbonates, connected to oxides, complexed with organic matter, mineral acids soluble and the rest) in sediments from the Vistula River estuary, the Gda?sk Basin and the Bornholm Deep were determined. The distribution of (239+240)Pu in analysed sediments samples was not uniform but dependent on its chemical form, depth and the sediment geomorphology. The highest amount of plutonium exists in middle parts of sediments and comes from the global atmospheric fallout from nuclear tests in 1958-1961. According to all analysed fractions, the biggest amount of (239+240)Pu was in the mobile form, connected to carbonate fractions from the Vistula River estuary, the Gulf of Gda?sk and the Bornholm Deep sediments. PMID:22612422

Strumi?ska-Parulska, Dagmara I; Skwarzec, Bogdan; Pawlukowska, Magdalena

2012-01-01

243

Plutonium stabilization and handling (PuSH)  

SciTech Connect

This Functional Design Criteria (FDC) addresses construction of a Stabilization and Packaging System (SPS) to oxidize and package for long term storage remaining plutonium-bearing special nuclear materials currently in inventory at the Plutonium Finishing Plant (PFP), and modification of vault equipment to allow storage of resulting packages of stabilized SNM for up to fifty years. The major sections of the project are: site preparation; SPS Procurement, Installation, and Testing; storage vault modification; and characterization equipment additions. The SPS will be procured as part of a Department of Energy nationwide common procurement. Specific design crit1460eria for the SPS have been extracted from that contract and are contained in an appendix to this document.

Weiss, E.V.

1997-01-23

244

Plutonium Elastic Moduli, Electron Localization, and Temperature  

SciTech Connect

In almost all materials, compression is accompanied naturally by stiffening. Even in materials with zero or negative thermal expansion, where warming is accompanied by volume contraction it is the volume change that primarily controls elastic stiffness. Not so in the metal plutonium. In plutonium, alloying with gallium can change the sign of thermal expansion, but for the positive thermal- expansion monoclinic phase as well as the face-centered-cubic phase with either sign of thermal expansion, and the orthorhombic phase, recent measurements of elastic moduli show soften on warming by an order of magnitude more than expected, the shear and compressional moduli track, and volume seems irrelevant. These effects point toward a novel mechanism for electron localization, and have important implication for the pressure dependence of the bulk compressibility. (authors)

Migliori, Albert; Mihut-Stroe, Izabella; Betts, Jon B. [National High Magnetic Field Lab, Los Alamos National Laboratory, MS E 536, Los Alamos, NM, 87545 (United States)

2008-07-01

245

CRITICALITY CURVES FOR PLUTONIUM HYDRAULIC FLUID MIXTURES  

SciTech Connect

This Calculation Note performs and documents MCNP criticality calculations for plutonium (100% {sup 239}Pu) hydraulic fluid mixtures. Spherical geometry was used for these generalized criticality safety calculations and three geometries of neutron reflection are: {sm_bullet}bare, {sm_bullet}1 inch of hydraulic fluid, or {sm_bullet}12 inches of hydraulic fluid. This document shows the critical volume and critical mass for various concentrations of plutonium in hydraulic fluid. Between 1 and 2 gallons of hydraulic fluid were discovered in the bottom of HA-23S. This HA-23S hydraulic fluid was reported by engineering to be Fyrquel 220. The hydraulic fluid in GLovebox HA-23S is Fyrquel 220 which contains phosphorus. Critical spherical geometry in air is calculated with 0 in., 1 in., or 12 inches hydraulic fluid reflection.

WITTEKIND WD

2007-10-03

246

Surplus Plutonium Disposition (SPD) Environmental Data Summary  

SciTech Connect

This document provides an overview of existing environmental and ecological information at areas identified as potential locations of the Savannah River Site's (SRS) Surplus Plutonium Disposition (SPD) facilities. This information is required to document existing environmental and baseline conditions from which SPD construction and operation impacts can be defined. It will be used in developing the required preoperational monitoring plan to be used at specific SPD facilities construction sites.

Fledderman, P.D.

2000-08-24

247

Plutonium-Based Nuclear Power and Nonproliferation  

Microsoft Academic Search

\\u000a The development of the nuclear power got its start in the 50ies based on 235 U thermal reactors of all the types, which had\\u000a been earlier developed for production of arm plutonium and tritium and for submarines. It was assumed that as thermal reactors\\u000a accumulated Pu and fast breeders were being mastered (their first power units were commissioned in 1972-1975

V. V. Orlov

248

Redox speciation of plutonium in natural waters  

Microsoft Academic Search

Data on the stability of Pu(V) as the dominant oxidation state of tracer concentrations of plutonium in natural waters is reviewed. Laboratory experiments for solutions of 0.1 and 1.0M (NaCl) ionic strength and pH 3–10 confirm the dominance of Pu(V) as the state in solution. Humics in the waters can cause reduction to Pu(IV).

G. R. Choppin

1991-01-01

249

Pollution around the Mayak Plutonium Production Complex  

Microsoft Academic Search

\\u000a Mayak, a production plant producing weapons-grade plutonium in the former USSR, was responsible for nuclear waste pollution\\u000a severely affecting inhabitants of the surrounding area. The internal exposure of the residents to strontium-90 (Sr-90) by\\u000a contamination of the Techa River is a disaster unrivaled elsewhere in the world. In this chapter, we report mainly on the\\u000a local investigations conducted in April

Jun Takada

250

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2010 CFR

...false General license: Plutonium-beryllium special form material. 71.23 Section...23 General license: Plutonium-beryllium special form material. (a) A...fissile material in the form of plutonium-beryllium (Pu-Be) special form...

2010-01-01

251

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false General license: Plutonium-beryllium special form material...Licenses § 71.23 General license: Plutonium-beryllium special form material...transport fissile material in the form of plutonium-beryllium (Pu-Be)...

2014-01-01

252

10 CFR 71.64 - Special requirements for plutonium air shipments.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Special requirements for plutonium air shipments. 71.64 Section 71... § 71.64 Special requirements for plutonium air shipments. (a) A package for the shipment of plutonium by air subject to §...

2011-01-01

253

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false General license: Plutonium-beryllium special form material...Licenses § 71.23 General license: Plutonium-beryllium special form material...transport fissile material in the form of plutonium-beryllium (Pu-Be)...

2012-01-01

254

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false General license: Plutonium-beryllium special form material...Licenses § 71.23 General license: Plutonium-beryllium special form material...transport fissile material in the form of plutonium-beryllium (Pu-Be)...

2011-01-01

255

10 CFR 71.23 - General license: Plutonium-beryllium special form material.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false General license: Plutonium-beryllium special form material...Licenses § 71.23 General license: Plutonium-beryllium special form material...transport fissile material in the form of plutonium-beryllium (Pu-Be)...

2013-01-01

256

10 CFR 71.64 - Special requirements for plutonium air shipments.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Special requirements for plutonium air shipments. 71.64 Section 71... § 71.64 Special requirements for plutonium air shipments. (a) A package for the shipment of plutonium by air subject to §...

2012-01-01

257

10 CFR 71.64 - Special requirements for plutonium air shipments.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Special requirements for plutonium air shipments. 71.64 Section 71... § 71.64 Special requirements for plutonium air shipments. (a) A package for the shipment of plutonium by air subject to §...

2014-01-01

258

10 CFR 71.64 - Special requirements for plutonium air shipments.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Special requirements for plutonium air shipments. 71.64 Section 71... § 71.64 Special requirements for plutonium air shipments. (a) A package for the shipment of plutonium by air subject to §...

2013-01-01

259

10 CFR 71.64 - Special requirements for plutonium air shipments.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Special requirements for plutonium air shipments. 71.64 Section 71... § 71.64 Special requirements for plutonium air shipments. (a) A package for the shipment of plutonium by air subject to §...

2010-01-01

260

PLUTONIUM FUEL PROCESSING AND FABRICATION FOR FAST CERAMIC REACTORS  

Microsoft Academic Search

A study was made of the processes available for fabrication of ;\\u000a plutonium-containing fuel from a fast ceramic reacter, and for chemical ;\\u000a reprocessing of irradiated fuel. Radiations from recycled plutonium are ;\\u000a evaluated. Adaptation of conventional glove-box handling procedures to the ;\\u000a fabrication of recycle plutonium appears practical. It is concluded that ;\\u000a acceptable costs are obtainable using moderate

E. L. Zebroski; H. W. Alter; G. D. Collins

1962-01-01

261

Pyrochemical investigations into recovering plutonium from americium extraction salt residues  

SciTech Connect

Progress into developing a pyrochemical technique for separating and recovering plutonium from spent americium extraction waste salts has concentrated on selective chemical reduction with lanthanum metal and calcium metal and on the solvent extraction of americium with calcium metal. Both techniques are effective for recovering plutonium from the waste salt, although neither appears suitable as a separation technique for recycling a plutonium stream back to mainline purification processes. 17 refs., 13 figs., 2 tabs.

Fife, K.W.; West, M.H.

1987-05-01

262

14. END VIEW OF THE PLUTONIUM STORAGE VAULT FROM THE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. END VIEW OF THE PLUTONIUM STORAGE VAULT FROM THE REMOTE CONTROL STATION. THE STACKER-RETRIEVER, A REMOTELY-OPERATED, MECHANIZED TRANSPORT SYSTEM, RETRIEVES CONTAINERS OF PLUTONIUM FROM SAFE GEOMETRY PALLETS STORED ALONG THE LENGTH OF THE VAULT. THE STACKER-RETRIEVER RUNS ALONG THE AISLE BETWEEN THE PALLETS OF THE STORAGE CHAMBER. (3/2/86) - Rocky Flats Plant, Plutonium Recovery Facility, Northwest portion of Rocky Flats Plant, Golden, Jefferson County, CO

263

New way to predict plutonium Finding could lead to  

E-print Network

New way to predict plutonium safety Finding could lead to improved storage of nuclear weapons of 2Science Front Page 2:14 PM ET Thursday, April 12, 2001 9/5/2003file://E:\\Homepages\\SavrasovHome\\Projects\\Research\\Plutonium, and Privacy Page 2 of 2Science Front Page 2:14 PM ET Thursday, April 12, 2001 9/5/2003file://E:\\Homepages\\SavrasovHome\\Projects\\Research\\Plutonium

Savrasov, Sergej Y.

264

SUSCEPTIBILIT MAGNTIQUE DE QUELQUES SULFURES ET OXYDES DE PLUTONIUM  

E-print Network

261. SUSCEPTIBILIT� MAGN�TIQUE DE QUELQUES SULFURES ET OXYDES DE PLUTONIUM Par GEORGES RAPHAEL et CHARLES DE NOVION, S.E.C.P.E.R., Section d'�tudes des Céramiques à base de Plutonium, Centre d susceptibilite magnétique des sulfures de plutonium : PuS, Pu3S4, PU2S3CXI PuS2. Ces composes non conduc- teurs

Paris-Sud XI, Université de

265

Plutonium speciation in water from Mono Lake, California  

USGS Publications Warehouse

The solubility of plutonium in Mono Lake water is enhanced by the presence of large concentrations of indigenous carbonate ions and moderate concentrations of fluoride ions. In spite of the complex chemical composition of this water, only a few ions govern the behavior of plutonium, as demonstrated by the fact that it was possible to duplicate plutonium speciation in a synthetic water containing only the principal components of Mono Lake water.

Cleveland, J.M.; Rees, T.F.; Nash, K.L.

1983-01-01

266

Microdosimetry of plutonium in beagle dog lung  

SciTech Connect

A better understanding of the microdosimetry of internally-deposited radionuclides should provide new clues to the complex relationships between organ dose distribution and early or late biological effects. Our current interest is the microdosimetry of plutonium and other alpha emitters in the lung. Since the lung is an inhomogeneous tissue, it was necessary to characterize the microscopic distributions of alveolar tissue, air space, and epithelial cell nuclei to define source-target parameters. A statistical representation of the microstructure of beagle dog lung was developed from automated image analysis of specimens from three healthy adult male dogs. The statistical distributions obtained constituted a data base from which it was possible to calculate both the energy dissipation of an alpha particle as it traversed a straight line path through pulmonary tissue, and the probability of intersecting a potentially sensitive biological site in the cell. Computer methods were modified to accomodate tissues with air space regions such as one finds in lung tissue. With the lung model description, these methods were used to determine probability density curves in specific energy for inhaled plutonium aerosols. It was assumed that the activity was randomly distributed on alveolar walls. Calculated examples are given for various activities of inhaled plutonium point sources deposited in lung tissue.

Fisher, D.R.; Roesch, W.C.

1980-08-01

267

A Plutonium-Contaminated Wound, 1985, USA  

SciTech Connect

A hand injury occurred at a U.S. facility in 1985 involving a pointed shaft (similar to a meat thermometer) that a worker was using to remove scrap solid plutonium from a plastic bottle. The worker punctured his right index finger on the palm side at the metacarpal-phalangeal joint. The wound was not through-and- through, although it was deep. The puncture wound resulted in deposition of ~48 kBq of alpha activity from the weapons-grade plutonium mixture with a nominal 12 to 1 Pu-alpha to {sup 241}Am-alpha ratio. This case clearly showed that DTPA was very effective for decorporation of plutonium and americium. The case is a model for management of wounds contaminated with transuranics: (1) a team approach for dealing with all of the issues surrounding the incident, including the psychological, (2) early surgical intervention for foreign-body removal, (3) wound irrigation with DTPA solution, and (4) early and prolonged DTPA administration based upon bioassay and in vivo dosimetry.

Doran M. Christensen, DO, REAC /TS Associate Director and Staff Physician Eugene H. Carbaugh, CHP, Staff Scientist, Internal Dosimetry Manager, Pacific Northwest National Laboratory, Richland, Washington

2012-02-02

268

Atomistic modeling of thermodynamic equilibrium of plutonium  

NASA Astrophysics Data System (ADS)

Plutonium metal has complex thermodynamic properties. Among its six allotropes at ambient pressure, the fcc delta-phase exhibits a wide range of anomalous behavior: extraordinarily high elastic anisotropy, largest atomic volume despite the close-packed structure, negative thermal expansion, strong elastic softening at elevated temperature, and extreme sensitivity to dilute alloying. An accurate description of these thermodynamic properties goes far beyond the current capability of first-principle calculations. An elaborate modeling strategy at the atomic level is hence an urgent need. We propose a novel atomistic scheme to model elemental plutonium, in particular, to reproduce the anomalous characteristics of the delta-phase. A modified embedded atom method potential is fitted to two energy-volume curves that represent the distinct electronic states of plutonium in order to embody the mechanism of the two-state model of Weiss, in line with the insight originally proposed by Lawson et al. [Philos. Mag. 86, 2713 (2006)]. By the use of various techniques in Monte Carlo simulations, we are able to provide a unified perspective of diverse phenomenological aspects among thermal expansion, elasticity, and phase stability.

Lee, Tongsik; Valone, Steve; Baskes, Mike; Chen, Shao-Ping; Lawson, Andrew

2012-02-01

269

Pyrochemical processing of plutonium. Technology review report  

SciTech Connect

Non-aqueous processes are now in routine use for direct conversion of plutonium oxide to metal, molten salt extraction of americium, and purification of impure metals by electrorefining. These processes are carried out at elevated temperatures in either refractory metal crucibles or magnesium-oxide ceramics in batch-mode operation. Direct oxide reduction is performed in units up to 700 gram PuO/sub 2/ batch size with molten calcium metal as the reductant and calcium chloride as the reaction flux. Americium metal is removed from plutonium metal by salt extraction with molten magnesium chloride. Electrorefining is used to isolate impurities from molten plutonium by molten salt ion transport in a controlled potential oxidation-reduction cell. Such cells can purify five or more kilograms of impure metal per 5-day electrorefining cycle. The product metal obtained is typically > 99.9% pure, starting from impure feeds. Metal scrap and crucible skulls are recovered by hydriding of the metallic residues and recovered either as impure metal or oxide feeds.

Coops, M.S.; Knighton, J.B.; Mullins, L.J.

1982-09-08

270

Characterizing Surplus US Plutonium for Disposition - 13199  

SciTech Connect

The United States (US) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition (OFMD) of the National Nuclear Security Administration (NNSA) and the DOE Office of Environmental Management (DOE-EM). SRNL manages a broad program of item tracking through process history, laboratory analysis, and non-destructive assay. A combination of analytical techniques allows SRNL to predict the isotopic and chemical properties that qualify materials for disposition through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The research also defines properties that are important for other disposition paths, including disposal to the Waste Isolation Pilot Plant (WIPP) as transuranic waste (TRUW) or to high-level waste (HLW) systems. (authors)

Allender, Jeffrey S. [Savannah River National Laboratory, Aiken SC 29808 (United States)] [Savannah River National Laboratory, Aiken SC 29808 (United States); Moore, Edwin N. [Moore Nuclear Energy, LLC, Savannah River Site, Aiken SC 29808 (United States)] [Moore Nuclear Energy, LLC, Savannah River Site, Aiken SC 29808 (United States)

2013-07-01

271

PLUTONIUM METALLIC FUELS FOR FAST REACTORS  

SciTech Connect

Early interest in metallic plutonium fuels for fast reactors led to much research on plutonium alloy systems including binary solid solutions with the addition of aluminum, gallium, or zirconium and low-melting eutectic alloys with iron and nickel or cobalt. There was also interest in ternaries of these elements with plutonium and cerium. The solid solution and eutectic alloys have most unusual properties, including negative thermal expansion in some solid-solution alloys and the highest viscosity known for liquid metals in the Pu-Fe system. Although metallic fuels have many potential advantages over ceramic fuels, the early attempts were unsuccessful because these fuels suffered from high swelling rates during burn up and high smearing densities. The liquid metal fuels experienced excessive corrosion. Subsequent work on higher-melting U-PuZr metallic fuels was much more promising. In light of the recent rebirth of interest in fast reactors, we review some of the key properties of the early fuels and discuss the challenges presented by the ternary alloys.

STAN, MARIUS [Los Alamos National Laboratory; HECKER, SIEGFRIED S. [Los Alamos National Laboratory

2007-02-07

272

TRACKING SURPLUS PLUTONIUM FROM WEAPONS TO DISPOSITION  

SciTech Connect

Supporting nuclear nonproliferation and global security principles, beginning in 1994 the United States has withdrawn more than 50 metric tons (MT) of government-controlled plutonium from potential use in nuclear weapons. The Department of Energy (DOE), including the National Nuclear Security Administration, established protocols for the tracking of this "excess" and "surplus" plutonium, and for reconciling the current storage and utilization of the plutonium to show that its management is consistent with the withdrawal policies. Programs are underway to ensure the safe and secure disposition of the materials that formed a major part of the weapons stockpile during the Cold War, and growing quantities have been disposed as waste, after which they are not included in traditional nuclear material control and accountability (NMC&A) data systems. A combination of resources is used to perform the reconciliations that form the basis for annual reporting to DOE, to U.S. Department of State, and to international partners including the International Atomic Energy Agency.

Allender, J.; Beams, J.; Sanders, K.; Myers, L.

2013-07-16

273

Characterizing surplus US plutonium for disposition  

SciTech Connect

The United States (US) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition (OFMD) of the National Nuclear Security Administration (NNSA) and the DOE Office of Environmental Management (DOE-EM). SRNL manages a broad program of item tracking through process history, laboratory analysis, and non-destructive assay. A combination of analytical techniques allows SRNL to predict the isotopic and chemical properties that qualify materials for disposition through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The research also defines properties that are important for other disposition paths, including disposal to the Waste Isolation Pilot Plant (WIPP) as transuranic waste (TRUW) or to high-level waste (HLW) systems.

Allender, Jeffrey S.; Moore, Edwin N.

2013-02-26

274

PUREX (Plutonium-Uranium Extraction) L-Cell concentrator corrosion evaluation  

SciTech Connect

Problems with solids plugging the piping associated with the E-L7-1 concentrator at the Plutonium-Uranium Extraction (PUREX) Plant were experienced shortly after it was put into use in 1971. The transfer line from the concentrator was first plugged in 1972. The PUREX Plant was shut down shortly thereafter after processing of available feed was finished. The plant was restarted in 1983, and plugging occurred again in early 1985. Both times, the transfer line was cleared by pulsing the fluid. The transfer line was replaced because of plugging in mid-1986 when pulsing failed to remove the plug. The concentrator, which is made of titanium, is used for the final concentration of the plutonium nitrate solution. The solids plugging the transfer line were identified as both the rutile and anatase forms of titanium dioxide. Ultrasonic examinations of titanium equipment in L-Cell showed that the concentrator wall thickness was decreasing as the acid refluxing area of the E-L7-1 tower was approached. The PUREX Plant Systems and Technology then requested the Plutonium Process Support Laboratories (PPSL) to set up and perform experiments to determine the cause(s) and possible corrective actions for the E-L7-1 corrosion. After testing samples of titanium and other metals under controlled conditions identical to E-L7-1 concentrator operation, zirconium was selected for long-term testing as a replacement for the tower section. Two long-term test apparatus were then built and tested on a pilot scale. 9 refs., 13 figs., 5 tabs.

Compton, J. A.; Delegard, C. H.

1990-05-01

275

Geomorphology of plutonium in the Northern Rio Grande  

SciTech Connect

Nearly all of the plutonium in the natural environment of the Northern Rio Grande is associated with soils and sediment, and river processes account for most of the mobility of these materials. A composite regional budget for plutonium based on multi-decadal averages for sediment and plutonium movement shows that 90 percent of the plutonium moving into the system is from atmospheric fallout. The remaining 10 percent is from releases at Los Alamos. Annual variation in plutonium flux and storage exceeds 100 percent. The contribution to the plutonium budget from Los Alamos is associated with relatively coarse sediment which often behaves as bedload in the Rio Grande. Infusion of these materials into the main stream were largest in 1951, 1952, 1957, and 1968. Because of the schedule of delivery of plutonium to Los Alamos for experimentation and weapons manufacturing, the latter two years are probably the most important. Although the Los Alamos contribution to the entire plutonium budget was relatively small, in these four critical years it constituted 71--86 percent of the plutonium in bedload immediately downstream from Otowi.

Graf, W.L. [Arizona Univ., Tempe, AZ (United States). Dept., of Geography

1993-03-01

276

Technical considerations and policy requirements for plutonium management  

SciTech Connect

The goals for plutonium management have changed dramatically over the past few years. Today, the challenge is focused on isolating plutonium from the environment and preparing it for permanent disposition. In parallel, the requirements for managing plutonium are rapidly changing. For example, there is a significant increase in public awareness on how facilities operate, increased attention to environmental safety and health (ES and H) concerns, greater interest in minimizing waste, more emphasis on protecting material from theft, providing materials for international inspection, and a resurgence of interest in using plutonium as an energy source. Of highest concern, in the immediate future, is protecting plutonium from theft or diversion, while the national policy on disposition is debated. These expanded requirements are causing a broadening of responsibilities within the Department of Energy (DOE) to include at least seven organizations. An unavoidable consequence is the divergence in approach and short-term goals for managing similar materials within each organization. The technology base does exist, properly, safely, and cost effectively to extract plutonium from excess weapons, residues, waste, and contaminated equipment and facilities, and to properly stabilize it. Extracting the plutonium enables it to be easily inventoried, packaged, and managed to minimize the risk of theft and diversion. Discarding excess plutonium does not sufficiently reduce the risk of diversion, and as a result, long-term containment of plutonium from the environment may not be able to be proven to the satisfaction of the public.

Christensen, D.C.; Dinehart, S.M.; Yarbro, S.L. [Los Alamos National Lab., NM (United States). Nuclear Materials Technology Div.

1995-12-31

277

Magnetic separation as a plutonium residue enrichment process  

SciTech Connect

We have subjected several plutonium contaminated residues to Open Gradient Magnetic Separation (OGMS) on an experimental scale. Separation of graphite, bomb reduction sand, and bomb reduction sand, and bomb reduction sand, slag, and crucible, resulted in a plutonium rich fraction and a plutonium lean fraction. The lean fraction varied between about 20% to 85% of the feed bulk. The plutonium content of the lean fraction can be reduced from about 2% in the feed to the 0.1% to 0.5% range dependent on the portion of the feed rejected to this lean fraction. These values are low enough in plutonium to meet economic discard limits and be considered for direct discard. Magnetic separation of direct oxide reduction and electrorefining pyrochemical salts gave less favorable results. While a fraction very rich in plutonium could be obtained, the plutonium content of the lean fraction was to high for direct discard. This may still have chemical processing applications. OGMS experiments at low magnetic field strength on incinerator ash did give two fractions but the plutonium content of each fraction was essentially identical. Thus, no chemical processing advantage was identified for magnetic separation of this residue. The detailed results of these experiments and the implications for OGMS use in recycle plutonium processing are discussed. 4 refs., 3 figs., 9 tabs.

Avens, L.R.; McFarlan, J.T.; Gallegos, U.F.

1989-01-01

278

30. VIEW OF A GLOVEBOX LINE USED IN PLUTONIUM OPERATIONS. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. VIEW OF A GLOVEBOX LINE USED IN PLUTONIUM OPERATIONS. SAFETY AND HEALTH CONCERNS WERE OF MAJOR IMPORTANCE AT THE PLANT, BECAUSE OF THE RADIOACTIVE NATURE OF THE MATERIALS USED. PLUTONIUM GIVES OFF ALPHA AND BETA PARTICLES, GAMMA PROTONS, NEUTRONS, AND IS ALSO PYROPHORIC. AS A RESULT, PLUTONIUM OPERATIONS ARE PERFORMED UNDER CONTROLLED CONDITIONS THAT INCLUDE CONTAINMENT, FILTERING, SHIELDING, AND CREATING AN INERT ATMOSPHERE. PLUTONIUM WAS HANDLED WITHIN GLOVEBOXES THAT WERE INTERCONNECTED AND RAN SEVERAL HUNDRED FEET IN LENGTH (5/5/70). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

279

Dissolution of plutonium oxide in nitric acid at high hydrofluoric acid concentrations  

SciTech Connect

The dissolution of plutonium dioxide in nitirc acid (HNO/sub 3/) at high hydrofluoric acid (HF) concentrations has been investigated. Dissolution rate curves were obtained using 12M HNO/sub 3/ and HF at concentrations varying from 0.05 to 1.0 molar. The dissolution rate increased with HF concentration up to 0.2M and then decreased at higher concentrations. There was very little plutonium dissolved at 0.7 and 1.0M HF because of the formation of insoluble PuF/sub 4/. Various oxidizing agents were added to 12M HNO/sub 3/-1M HF dissolvent to oxidize Pu(IV) to Pu(VI) and prevent the formation of PuF/sub 4/. Ceric (Ce(IV)) and silver (Ag(II)) ions were the most effective in dissolving PuO/sub 2/. Although these two oxidants greatly increased the dissolution rate, the rates were not as rapid as those obtained with 12M HNO/sub 3/-0.2M HF.

Kazanjian, A.R.; Stevens, J.R.

1984-06-15

280

Plutonium-uranium mixed oxide characterization by coupling micro-X-ray diffraction and absorption investigations  

NASA Astrophysics Data System (ADS)

Plutonium-uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The potential differences of metal redox state and microstructural developments of the matrix before and after irradiation are commonly analysed by electron probe microanalysis. In this work the structure and next-neighbor atomic environments of Pu and U oxide features within unirradiated homogeneous MOX and irradiated (60 MW d kg -1) MOX samples was analysed by micro-X-ray fluorescence (?-XRF), micro-X-ray diffraction (?-XRD) and micro-X-ray absorption fine structure (?-XAFS) spectroscopy. The grain properties, chemical bonding, valences and stoichiometry of Pu and U are determined from the experimental data gained for the unirradiated as well as for irradiated fuel material examined in the center of the fuel as well as in its peripheral zone (rim). The formation of sub-grains is observed as well as their development from the center to the rim (polygonization). In the irradiated sample Pu remains tetravalent (>95%) and no (<5%) Pu(V) or Pu(VI) can be detected while the fuel could undergo slight oxidation in the rim zone. Any slight potential plutonium oxidation is buffered by the uranium dioxide matrix while locally fuel cladding interaction could also affect the redox of the fuel.

Degueldre, C.; Martin, M.; Kuri, G.; Grolimund, D.; Borca, C.

2011-09-01

281

Real-time measurement of plutonium in air by direct-inlet surface ionization mass spectrometry. Status report  

SciTech Connect

A new technique is being developed for monitoring low-level airborne plutonium on a real-time basis. The technique is based on surface ionization mass spectrometry of airborne particles. It will be capable of measuring plutonium concentrations below the maximum permissible concentration (MPC) level. A complete mass spectrometer was designed and constructed for this purpose. Major components which were developed and made operational for the instrument include an efficient inlet for directly sampling particles in air, a wide dynamic range ion detector and a minicomputer-based ion-burst measurement system. Calibration of the direct-inlet mass spectrometer (DIMS) was initiated to establish the instrument's response to plutonium dioxide as a function of concentration and particle size. This work revealed an important problem - bouncing of particles upon impact with the ionizing filament. Particle bounce results in a significant loss of measurement sensitivity. The feasibility of using an oven ionizer to overcome the particle bounce problem has been demonstrated. A rhenium oven ionizer was designed and constructed for the purpose of trapping particles which enter via the direct inlet. High-speed particles were trapped in the oven yielding a measurement sensitivity comparable to that for particles which are preloaded. Development of the Pu DIMS can now be completed by optimizing the oven design and calibrating the instrument's performance with UO/sub 2/ and CeO/sub 2/ particles as analogs to PuO/sub 2/ particles.

Stoffels, J.J.

1980-04-01

282

Carbon dioxide affects global ecology  

Microsoft Academic Search

Man's activities are changing the carbon dioxide and oxygen content of the entire atmosphere. These changes may, in turn, affect worldwide weather and the growth of plants. Under normal conditions, the amounts of carbon dioxide and oxygen in the atmosphere remain approximately in equilibrium on a year-to-year basis. The atmosphere today contains about 21% oxygen and about 0.032% carbon dioxide

Eugene K. Peterson

1969-01-01

283

Plutonium and Cesium Colloid Mediated Transport  

NASA Astrophysics Data System (ADS)

Plutonium and cesium have been released to the environment at many different locations worldwide and are present in spent fuel at significant levels. Accurate understanding of the mechanisms that control their fate and transport in the environment is important for the management of contaminated sites, for forensic applications, and for the development of robust repositories for the disposal of spent nuclear fuel and nuclear waste. Plutonium, which can be present in the environment in multiple oxidations states and various chemical forms including amorphous oxy(hydr)oxide phases, adsorbs/adheres very strongly to geological materials and is usually immobile in all its chemical forms. However, when associated with natural colloids, it has the potential to migrate significant distances from its point of release. Like plutonium, cesium is not very mobile and tends to remain adhered to geological materials near its release point, although its transport can be enhanced by natural colloids. However, the reactivity of plutonium and cesium are very different, so their colloid-mediated transport might be significantly different in subsurface environments. In this study, we performed controlled experiments in two identically-prepared columns; one dedicated to Pu and natural colloid transport experiments, and the other to Cs and colloid experiments. Multiple flow-through experiments were conducted in each column, with the effluent solutions being collected and re-injected into the same column two times to examine the persistence and scaling behavior of the natural colloids, Pu and Cs. The data show that that a significant fraction of colloids were retained in the first elution through each column, but the eluted colloids collected from the first run transported almost conservatively in subsequent runs. Plutonium transport tracked natural colloids in the first run but deviated from the transport of natural colloids in the second and third runs. Cesium transport tracked natural colloid transport in all re-injections. The data will be discussed in terms of natural colloid properties, including size distribution and electrokinetic properties, as well as the reactive transport behavior of Pu and Cs. We will also discuss the implications of the results for colloid-mediated contaminant transport, management of contaminated sites and forensic data interpretation.

Boukhalfa, H.; Dittrich, T.; Reimus, P. W.; Ware, D.; Erdmann, B.; Wasserman, N. L.; Abdel-Fattah, A. I.

2013-12-01

284

Process for sequestering carbon dioxide and sulfur dioxide  

DOEpatents

A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

Maroto-Valer, M. Mercedes (State College, PA); Zhang, Yinzhi (State College, PA); Kuchta, Matthew E. (State College, PA); Andresen, John M. (State College, PA); Fauth, Dan J. (Pittsburgh, PA)

2009-10-20

285

21 CFR 73.575 - Titanium dioxide.  

Code of Federal Regulations, 2010 CFR

...Titanium dioxide. (a) Identity. (1) The color additive titanium dioxide is synthetically prepared TiO2...subject to the following restrictions: (1) The quantity of titanium dioxide does not exceed 1 percent by weight of the food....

2010-04-01

286

21 CFR 184.1240 - Carbon dioxide.  

Code of Federal Regulations, 2010 CFR

...Drugs 3 2010-04-01 2009-04-01 true Carbon dioxide. 184.1240 Section 184.1240 Food...Specific Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2 , CAS...

2010-04-01

287

21 CFR 73.3126 - Titanium dioxide.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Titanium dioxide. 73.3126 Section 73... Medical Devices § 73.3126 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide (CAS Reg. No....

2011-04-01

288

21 CFR 73.1575 - Titanium dioxide.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Titanium dioxide. 73.1575 Section...CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in...

2010-04-01

289

21 CFR 73.1575 - Titanium dioxide.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Titanium dioxide. 73.1575 Section...CERTIFICATION Drugs § 73.1575 Titanium dioxide. (a) Identity and specifications. (1) The color additive titanium dioxide shall conform in...

2011-04-01

290

21 CFR 73.3126 - Titanium dioxide.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Titanium dioxide. 73.3126 Section 73... Medical Devices § 73.3126 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide (CAS Reg. No....

2014-04-01

291

21 CFR 73.3126 - Titanium dioxide.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Titanium dioxide. 73.3126 Section 73... Medical Devices § 73.3126 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide (CAS Reg. No....

2012-04-01

292

21 CFR 73.3126 - Titanium dioxide.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Titanium dioxide. 73.3126 Section 73... Medical Devices § 73.3126 Titanium dioxide. (a) Identity and specifications. The color additive titanium dioxide (CAS Reg. No....

2013-04-01

293

Chemical species of plutonium in Hanford radioactive tank waste  

SciTech Connect

Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other potential complexants. The sodium nitrate and sodium phosphate salts that form most of the salt cake layers have little interaction with plutonium in the wastes and contain relatively small plutonium concentrations. For these reasons the authors consider plutonium species in the sludges and supernate solutions only. The low concentrations of plutonium in waste tank supernate solutions and in the solid sludges prevent identification of chemical species of plutonium by ordinary analytical techniques. Spectrophotometric measurements are not sensitive enough to identify plutons oxidation states or complexes in these waste solutions. Identification of solid phases containing plutonium in sludge solids by x-ray diffraction or by microscopic techniques would be extremely difficult. Because of these technical problems, plutonium speciation was extrapolated from known behavior observed in laboratory studies of synthetic waste or of more chemically simple systems.

Barney, G.S.

1997-10-22

294

Weapons-grade plutonium dispositioning. Volume 4. Plutonium dispositioning in light water reactors  

Microsoft Academic Search

This study is in response to a request by the Reactor Panel Subcommittee of the National Academy of Sciences (NAS) Committee on International Security and Arms Control (CISAC) to evaluate the feasibility of using plutonium fuels (without uranium) for disposal in existing conventional or advanced light water reactor (LWR) designs and in low temperature\\/pressure LWR designs that might be developed

J. W. Sterbentz; C. S. Olsen; U. P. Sinha

1993-01-01

295

Ultra-small plutonium oxide nanocrystals: an innovative material in plutonium science.  

PubMed

Apart from its technological importance, plutonium (Pu) is also one of the most intriguing elements because of its non-conventional physical properties and fascinating chemistry. Those fundamental aspects are particularly interesting when dealing with the challenging study of plutonium-based nanomaterials. Here we show that ultra-small (3.2±0.9?nm) and highly crystalline plutonium oxide (PuO2 ) nanocrystals (NCs) can be synthesized by the thermal decomposition of plutonyl nitrate ([PuO2 (NO3 )2 ]?3?H2 O) in a highly coordinating organic medium. This is the first example reporting on the preparation of significant quantities (several tens of milligrams) of PuO2 NCs, in a controllable and reproducible manner. The structure and magnetic properties of PuO2 NCs have been characterized by a wide variety of techniques (powder X-ray diffraction (PXRD), X-ray absorption fine structure (XAFS), X-ray absorption near edge structure (XANES), TEM, IR, Raman, UV/Vis spectroscopies, and superconducting quantum interference device (SQUID) magnetometry). The current PuO2 NCs constitute an innovative material for the study of challenging problems as diverse as the transport behavior of plutonium in the environment or size and shape effects on the physics of transuranium elements. PMID:25042621

Hudry, Damien; Apostolidis, Christos; Walter, Olaf; Janssen, Arne; Manara, Dario; Griveau, Jean-Christophe; Colineau, Eric; Vitova, Tonya; Prüssmann, Tim; Wang, Di; Kübel, Christian; Meyer, Daniel

2014-08-11

296

Contribution of water vapor pressure to pressurization of plutonium dioxide storage containers  

Microsoft Academic Search

Pressurization of long-term storage containers filled with materials meeting the US DOE storage standard is of concern.1,2 For example, temperatures within storage containers packaged according to the standard and contained in 9975 shipping packages that are stored in full view of the sun can reach internal temperatures of 250 °C.3 Twenty five grams of water (0.5 wt.%) at 250 °C

D. Kirk Veirs; John S. Morris; Dane R. Spearing

2000-01-01

297

Dosimetry of inhaled plutonium-239 dioxide in rodent lung: a morphometric study  

SciTech Connect

Morphometric analysis of rat and hamster lung did not demonstrate any extensive changes in lung composition or structure following inhalation exposure to /sup 239/Pu0/sub 2/ at levels near that for maximum tumor yield in rats. The problem of dosimetry for this compound thus appears to be relatively uncomplicated by any major radiation-induced pathological alterations in the lung. Rat and hamster lung were found to be similar in structure and composition, with few significant differences which could be directly related to the different tumor responses. The distribution of /sup 239/Pu0/sub 2/ particles was not uniform in all regions of the lung; thus estimation of the dose to specific tissues or regions within the lung requires a correction for this effect. Species differences were found for particle distribution in the subpleural region and major airways, and in the spatial association of particles, both of which may affect the tumor development process. These regions contain the principal target cells for tumor production and serve as foci for the origin of tumors. Different dose distributions within these regions may therefore explain, at least in part, the difference in tumor response to inhaled /sup 239/Pu0/sub 2/ for rats and hamsters.

Rhoads, K.

1979-06-01

298

Hypoadrenocorticism in beagles exposed to aerosols of plutonium-238 dioxide by inhalation  

SciTech Connect

Hypoadrenocorticism, known as Addison`s disease in humans, was diagnosed in six beagles after inhalation of at least 1.7 kBq/g lung of {sup 238}PuO{sub 2}. Histological examination of adrenal gland specimens obtained at necropsy revealed marked adrenal cortical atrophy in all cases. Autoadiographs showed only slight {alpha}-particle activity. Although the pathogenesis of adrenal cortical atrophy in these dogs is unclear, there is evidence to suggest an automimmune disorder linked to damage resulting from {alpha}-particle irradiation to the lymphatic system.

Weller, R.E.; Buschbom, R.L.; Dagle, G.E. [Pacific Northwest National Lab., Richland, WA (United States)] [and others

1996-12-01

299

Primary liver tumors in beagle dogs exposed by inhalation to aerosols of plutonium-238 dioxide  

SciTech Connect

Primary liver tumors developed in Beagle dogs exposed by inhalation to aerosols of /sup 238/PuO/sub 2/. Initial deposition of /sup 238/PuO/sub 2/ in the respiratory tract was followed by translocation of a portion of the /sup 238/Pu to the liver and skeleton, which resulted in a large dose commitment and tumor risk to all three tissues. In a population of 144 dogs exposed to /sup 238/PuO/sub 2/, 112 dogs died or were killed 4000 days after /sup 238/Pu exposure, 100 dogs had osteosarcoma, and 28 dogs had lung cancers. At increasing times after exposure, however, liver lesions have become more pronounced. Ten primary liver tumors in nine animals were diagnosed in the dogs dying before 4000 days after exposure. An additional five primary liver tumors in three dogs occurred in 9 animals killed after 4000 days after exposure. The majority of these tumors have been fibrosarcomas. The liver tumors were usually not the cause of death, and rarely metastasized. The occurrence of liver tumors in this study indicates that /sup 238/Pu is an effective hepatic carcinogen. Liver carcinogenesis is assuming an increasing importance in this study at late times after inhalation exposure. These results suggest that the liver may be an important organ at risk for the development of neoplasia in humans at time periods long after inhalation of /sup 238/Pu.

Gillett, N.A.; Muggenburg, B.A.; Mewhinney, J.A.; Hahn, F.F.; Seiler, F.A.; Boecker, B.B.; McClellan, R.O.

1988-11-01

300

CONVOLUTION APPROACH TO EVALUATING INTAKE DISTRIBUTIONS FOR INHALED PLUTONIUM DIOXIDE FOR THE STOCHASTIC INTAKE PARADIGM  

EPA Science Inventory

For airborne toxic particles, the stochastic intake (SI) paradigm involves relatively low numbers of particles that are presented for inhalation. Each person at risk may inhale a different number of particles, including zero particles. For such exposure scenarios, probabilistic d...

301

Reaction products of chlorine dioxide.  

PubMed Central

Inspection of the available literature reveals that a detailed investigation of the aqueous organic chemistry of chlorine dioxide and systematic identification of products formed during water disinfection has not been considered. This must be done before an informed assessment can be made of the relative safety of using chlorine dioxide as a disinfectant alternative to chlorine. Although trihalomethanes are generally not formed by the action of chlorine dioxide, the products of chlorine dioxide treatment of organic materials are oxidized species, some of which also contain chlorine. The relative amounts of species types may depend on the amount of chlorine dioxide residual maintained and the concentration and nature of the organic material present in the source water. The trend toward lower concentrations of chlorinated by-products with increasing ClO2 concentration, which was observed with phenols, has not been observed with natural humic materials as measured by the organic halogen parameter. Organic halogen concentrations have been shown to increase with increasing chlorine dioxide dose, but are much lower than those observed when chlorine is applied. Aldehydes have been detected as apparent by-products of chlorine dioxide oxidation reactions in a surface water that is a drinking water source. Some other nonchlorinated products of chlorine dioxide treatment may be quinones and epoxides. The extent of formation of these moieties within the macromolecular humic structure is also still unknown. PMID:7151750

Stevens, A A

1982-01-01

302

Carbon dioxide and terrestrial ecosystems  

Microsoft Academic Search

This book is a summary of the current research which addresses the effects of elevated carbon dioxide on terrestrial ecosystems and an identification of significant unresolved issues. Chapters address the carbon dioxide effects on trees and forests, unmanaged herbaceous ecosystems, and crops. Included are experimental studies, conceptual models, general mathematical models, dynamic simulation models.

G. W. Koch; H. A. Mooney

1996-01-01

303

Carbon dioxide adsorbent study  

NASA Technical Reports Server (NTRS)

A study was initiated on the feasibility of using the alkali metal carbonate - bi-carbonate solid-gas reaction to remove carbon dioxide from the atmosphere of an EVA life support system. The program successfully demonstrates that carbon dioxide concentrations could be maintained below 0.1 mole per cent using this chemistry. Further a practical method for distributing the carbonates in a coherent sheet form capable of repeated regeneration (50 cycles) at modest temperatures (423 K), without loss in activity was also demonstrated. Sufficiently high reaction rates were shown to be possible with the carbonate - bi-carbonate system such that EVA hardware could be readily designed. Experimental and design data were presented on the basis of which two practical units were designed. In addition to conventional thermally regenerative systems very compact units using ambient temperature cyclic vacuum regeneration may also be feasible. For a one man - 8 hour EVA unit regenerated thermally at the base ship a system volume of 14 liters is estimated.

Onischak, M.; Baker, B. S.

1973-01-01

304

Carbon dioxide and climate  

SciTech Connect

Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

Not Available

1990-10-01

305

Plutonium in the arctic marine environment--a short review.  

PubMed

Anthropogenic plutonium has been introduced into the environment over the past 50 years as the result of the detonation of nuclear weapons and operational releases from the nuclear industry. In the Arctic environment, the main source of plutonium is from atmospheric weapons testing, which has resulted in a relatively uniform, underlying global distribution of plutonium. Previous studies of plutonium in the Kara Sea have shown that, at certain sites, other releases have given rise to enhanced local concentrations. Since different plutonium sources are characterised by distinctive plutonium-isotope ratios, evidence of a localised influence can be supported by clear perturbations in the plutonium-isotope ratio fingerprints as compared to the known ratio in global fallout. In Kara Sea sites, such perturbations have been observed as a result of underwater weapons tests at Chernaya Bay, dumped radioactive waste in Novaya Zemlya, and terrestrial runoff from the Ob and Yenisey Rivers. Measurement of the plutonium-isotope ratios offers both a means of identifying the origin of radionuclide contamination and the influence of the various nuclear installations on inputs to the Arctic, as well as a potential method for following the movement of water and sediment loads in the rivers. PMID:15258672

Skipperud, Lindis

2004-06-18

306

Processing of Non-PFP Plutonium Oxide in Hanford Plants  

SciTech Connect

Processing of non-irradiated plutonium oxide, PuO2, scrap for recovery of plutonium values occurred routinely at Hanford’s Plutonium Finishing Plant (PFP) in glovebox line operations. Plutonium oxide is difficult to dissolve, particularly if it has been high-fired; i.e., calcined to temperatures above about 400°C and much of it was. Dissolution of the PuO2 in the scrap typically was performed in PFP’s Miscellaneous Treatment line using nitric acid (HNO3) containing some source of fluoride ion, F-, such as hydrofluoric acid (HF), sodium fluoride (NaF), or calcium fluoride (CaF2). The HNO3 concentration generally was 6 M or higher whereas the fluoride concentration was ~0.5 M or lower. At higher fluoride concentrations, plutonium fluoride (PuF4) would precipitate, thus limiting the plutonium dissolution. Some plutonium-bearing scrap also contained PuF4 and thus required no added fluoride. Once the plutonium scrap was dissolved, the excess fluoride was complexed with aluminum ion, Al3+, added as aluminum nitrate, Al(NO3)3•9H2O, to limit collateral damage to the process equipment by the corrosive fluoride. Aluminum nitrate also was added in low quantities in processing PuF4.

Jones, Susan A.; Delegard, Calvin H.

2011-03-10

307

Advanced fuels for plutonium management in pressurized water reactors  

Microsoft Academic Search

Several fuel concepts are under investigation at CEA with the aim of manage plutonium inventories in pressurized water reactors. This options range from the use of mature technologies like MOX adapted in the case of MOX-EUS (enriched uranium support) and COmbustible Recyclage A ILot (CORAIL) assemblies to more innovative technologies using IMF like DUPLEX and advanced plutonium assembly (APA). The

A. Vasile; Ph Dufour; H Golfier; J. P Grouiller; J. L Guillet; Ch Poinot; G Youinou; A Zaetta

2003-01-01

308

X-ray diffraction study of pure plutonium under pressure  

Microsoft Academic Search

Atomic volume and bulk modulus represent basic cohesion properties of a material and are therefore linked to many other physical properties. However, large discrepancies are found in the literature regarding values for the bulk modulus of pure plutonium (?-phase). New X-ray diffraction measurements of plutonium in diamond anvil cell are presented and the isothermal bulk modulus is extracted.

Ph. Faure; C. Genestier

2009-01-01

309

Recommended plutonium release fractions from postulated fires. Final report  

SciTech Connect

This report was written at the request of EG&G Rocky Flats, Inc. in support of joint emergency planning for the Rocky Flats Plant (RFP) by EG&G and the State of Colorado. The intent of the report is to provide the State of Colorado with an independent assessment of any respirable plutonium releases that might occur in the event of a severe fire at the plant. Fire releases of plutonium are of interest because they have been used by EG&G to determine the RFP emergency planning zones. These zones are based on the maximum credible accident (MCA) described in the RFP Final Environmental Impact Statement (FEIS) of 1980, that MCA is assumed to be a large airplane crashing into a RFP plutonium building.The objective of this report was first, to perform a worldwide literature review of relevant release experiments from 1960 to the present and to summarize those findings, and second, to provide recommendations for application of the experimental data to fire release analyses at Rocky Flats. The latter step requires translation between experimental and expected RFP accident parameters, or ``scaling.`` The parameters of particular concern are: quantities of material, environmental parameters such as the intensity of a fire, and the physico-chemical forms of the plutonium. The latter include plutonium metal, bulk plutonium oxide powder, combustible and noncombustible wastes contaminated with plutonium oxide powder, and residues from plutonium extraction processes.

Kogan, V.; Schumacher, P.M.

1993-12-01

310

26. Plutonium Recovery From Contaminated Materials, Architectural Elevations, Sections & ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

26. Plutonium Recovery From Contaminated Materials, Architectural Elevations, Sections & Dets., Building 232-Z, U.S. Atomic Energy Commission, Hanford Atomic Products Operation, General Electric Company, Dwg. No. H-2-23106, 1959. - Plutonium Finishing Plant, Waste Incinerator Facility, 200 West Area, Richland, Benton County, WA

311

25. Plutonium Recovery From Contaminated Materials, Architectural Plans & Details, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. Plutonium Recovery From Contaminated Materials, Architectural Plans & Details, Building 232-Z, U.S. Atomic Energy Commission, Hanford Atomic Products Operation, General Electric Company, Dwg. No. H-2-23105, 1959. - Plutonium Finishing Plant, Waste Incinerator Facility, 200 West Area, Richland, Benton County, WA

312

10. VIEW OF THE INSTALLATION OF PLUTONIUM FABRICATION ROLLING MILL. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. VIEW OF THE INSTALLATION OF PLUTONIUM FABRICATION ROLLING MILL. THE MILL ROLLED INGOTS INTO SHEETS THAT WERE THEN CUT INTO CIRCLE BLANKS TO BE PASSED THROUGH THE CENTER LINE FOR PRESSING. (2/19/63) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

313

A plutonium-based single-molecule magnet.  

PubMed

The magnetic properties of the 5f(5) [tris-(tri-1-pyrazolylborato)-plutonium(III)] complex have been investigated by ac susceptibility measurements, showing it to be the first plutonium single-molecule magnet; its magnetic relaxation slows down with decreasing temperature through a thermally activated mechanism followed by a quantum tunnelling regime below 5 K. PMID:24927255

Magnani, N; Colineau, E; Griveau, J-C; Apostolidis, C; Walter, O; Caciuffo, R

2014-08-01

314

Fuel bundle design for enhanced usage of plutonium fuel  

DOEpatents

A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced.

Reese, Anthony P. (San Jose, CA); Stachowski, Russell E. (Fremont, CA)

1995-01-01

315

Global estimation of potential unreported plutonium in thermal research reactors  

Microsoft Academic Search

As of November, 1993, 303 research reactors (research, test, training, prototype, and electricity producing) were operational worldwide; 155 of these were in non-nuclear weapon states. Of these 155 research reactors, 80 are thermal reactors that have a power rating of 1 MW(th) or greater and could be utilized to produce plutonium. A previously published study on the unreported plutonium production

J. S. Dreicer; D. A. Rutherford

1996-01-01

316

Plutonium Protection System (PPS). Volume 2. Hardware description. Final report  

Microsoft Academic Search

The Plutonium Protection System (PPS) is an integrated safeguards system developed by Sandia Laboratories for the Department of Energy, Office of Safeguards and Security. The system is designed to demonstrate and test concepts for the improved safeguarding of plutonium. Volume 2 of the PPS final report describes the hardware elements of the system. The major areas containing hardware elements are

Miyoshi

1979-01-01

317

Procedure for plutonium determination using Pu(VI) spectra  

SciTech Connect

This document describes a simple spectrophotometric method for determining total plutonium in nitric acid solutions based on the spectrum of Pu(VI). Plutonium samples in nitric acid are oxidized to Pu(VI) with Ce(IV) and the net absorbance at the 830 nm peak is measured.

Walker, L.F.; Temer, D.J.; Jackson, D.D.

1996-09-01

318

ANNUAL REPORT. PLUTONIUM SPECIATION, SOLUBILIZATION, AND MIGRATION IN SOILS  

EPA Science Inventory

This report summarizes work performed in the first year of a three-year project. In this year we are focusing on the following: 1) the interactions between plutonium compounds and redox active iron and manganese minerals, 2) the interactions between plutonium compounds and sedime...

319

Massive subcritical compact arrays of plutonium metal  

SciTech Connect

Two experimental critical-approach programs are reported. Both were performed at the Rocky Flats Plant near Denver, Colorado; and both date back to the late 1960s. Both involve very large arrays of massive plutonium ingots. These ingots had been cast in the foundry at the Rocky Flats Plant as part of their routine production operations; they were not specially prepared for either study. Consequently, considerable variation in ingot mass is encountered. This mass varied between approximately 7 kg and a little more than 10 kg. One program, performed in the spring of 1969, involved stacked arrays of ingots contained within cylindrical, disk-shaped, thin, steel cans. This program studied four arrays defined by the pattern of steel cans in a single layer. The four were: 1 x N, 3 x N, 2 x 2 x N, and 3 x 3 x N. The second was a tightly-packed, triangular-pitched patterns; the last two were square-pitched patterns. The other program, performed about a year earlier, involved similar ingots also contained in similar steel cans, but these canned plutonium ingots were placed in commercial steel drums. This study pertained to one-, two-, and three-layered horizontal arrays of drums. All cases proved to be well subcritical. Most would have remained subcritical had the parameters of the array under study been continued infinitely beyond the reciprocal multiplication safety limit. In one case for the drum arrays, an uncertain extrapolation of the data of the earlier program suggests that criticality might have eventually been attained had several thousand additional kilograms of plutonium been available for use.

Rothe, R.E.

1998-04-01

320

Hydride-catalyzed corrosion of plutonium by air: Initiation by plutonium monoxide monohydride  

SciTech Connect

Chemistry and kinetics of air reactions with plutonium monoxide monohydride (PuOH) and with mixtures of the oxide hydride and plutonium metal are defined by results of pressure-volume-temperature (PVT) measurements. Test with specimens prepared by total and partial corrosion of plutonium in 0.05 M sodium chloride solution show that reaction of residual water continues to generate H{sub 2} after liquid water is removed by evacuation. Rapid exposure of PuOH to air at room temperature does not produce a detectable reaction, but similar exposure of a partially corroded metal sample containing Pu and PuOH results in hydride (PuH{sub x})-catalyzed corrosion of the residual Pu. Kinetics of he first-order reaction resulting in formation of the PuH{sub x} catalyst and of the indiscriminate reaction of N{sub 2} and O{sub 2} with plutonium metal are defined. The rate of the catalyzed Pu+air reaction is independent of temperature (E{sub a} = 0), varies as the square of air pressure, and equals 0.78 {+-} 0.03 g Pu/cm{sup 2} min in air at one atmosphere. The absence of pyrophoric behavior for PuOH and differences in the reactivities of PuOH and PuOH + Pu mixtures are attributed to kinetic control by gaseous reaction products. Thermodynamic properties of the oxide hydride are estimated, particle size distributions of corrosion products are presented, and potential hazards associated with products formed by aqueous corrosion of plutonium are discussed.

Allen, T.H.; Haschke, J.M.

1998-06-01

321

Prototype fast neutron counter for the assay of impure plutonium  

SciTech Connect

A fast coincident neutron counter using liquid scintillators and gamma-ray/neutron pulse-shape discrimination has been constructed for the analysis of plutonium samples with unknown self-multiplication and (..cap alpha..,n) production. The counter was used to measure plutonium-bearing materials that cover a range of masses and (..cap alpha..,n) reaction rates of importance to the safeguards community. Measured values of the /sup 240/Pu effective mass differed, on average, from their declared values by 0.4% for plutonium oxides and by -2.2% for metal and MgO-loaded samples. Poorer results were obtained for materials with large (..cap alpha..,n) reaction rates and low self-multiplication such as plutonium ash and plutonium fluoride.

Wachter, J.R.; Adams, E.L.; Ensslin, N.

1987-01-01

322

Development of advanced mixed oxide fuels for plutonium management  

SciTech Connect

A number of advanced Mixed Oxide (MOX) fuel forms are currently being investigated at Los Alamos National Laboratory that have the potential to be effective plutonium management tools. Evolutionary Mixed Oxide (EMOX) fuel is a slight perturbation on standard MOX fuel, but achieves greater plutonium destruction rates by employing a fractional nonfertile component. A pure nonfertile fuel is also being studied. Initial calculations show that the fuel can be utilized in existing light water reactors and tailored to address different plutonium management goals (i.e., stabilization or reduction of plutonium inventories residing in spent nuclear fuel). In parallel, experiments are being performed to determine the feasibility of fabrication of such fuels. Initial EMOX pellets have successfully been fabricated using weapons-grade plutonium.

Eaton, S.; Beard, C.; Buksa, J.; Butt, D.; Chidester, K.; Havrilla, G.; Ramsey, K.

1997-06-01

323

23. AERIAL VIEW LOOKING SOUTHEAST AT THE PLUTONIUM OPERATION BUILDINGS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. AERIAL VIEW LOOKING SOUTHEAST AT THE PLUTONIUM OPERATION BUILDINGS 771, 776/777, AND 707. BUILDING 771, IN THE FOREGROUND, WAS BUILT IN 1952 TO HOUSE ALL PLUTONIUM OPERATIONS. BY 1956, BUILDING 771 WAS NO LONGER ADEQUATE FOR PRODUCTION DEMANDS. BUILDING 776/777, TO THE SOUTH OF BUILDING 771, WAS CONSTRUCTED TO HOUSE PLUTONIUM FABRICATION AND FOUNDRY OPERATIONS. PLUTONIUM RECOVERY REMAINED IN BUILDING 771. BY 1967, CONSTRUCTION ON BUILDING 707, TO THE SOUTH OF BUILDING 776/777, BEGAN AS PRODUCTION LEVELS CONTINUED TO EXPAND NECESSITATING THE NEED FOR ADDITIONAL PLUTONIUM FABRICATION SPACE (7/1/69). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

324

Low-temperature synthesis of plutonium hexafluoride  

SciTech Connect

The preparation of PuF/sub 6/ by the action of dioxygen difluoride (O/sub 2/F/sub 2/) on plutonium fluorides, oxides, and oxyfluorides at room temperature or below is described. Previously, direct synthesis of PuF/sub 6/ could only be achieved by high temperature (>300/sup 0/C) fluorination and by microwave or photolytic generation of fluorine atoms. Six experiments are described that illustrate the potency of O/sub 2/F/sub 2/ which is the property of this compound that indicates potential application in the nuclear industry.

Malm, J.G.; Eller, P.G.; Asprey, L.B.

1984-05-02

325

Plutonium research program, fiscal year 1970  

SciTech Connect

This report contains a compilation of unclassified plutonium programs underway in FY 1970 in the field of materials science. It includes work in ceramics, metallurgy, solid state physics and physical chemistry. Information on each of the programs is given in five sub-headings: scope of the work; technical effort in manyears; primary class of materials studied; person(s) to contact for further information; and reports and publications. All the work listed is restricted to either research or long range development and not applied or hardware-type projects.

Not Available

1970-03-01

326

Applications of molten salts in plutonium processing  

SciTech Connect

Plutonium is efficiently recovered from scrap at Los Alamos by a series of chemical reactions and separations conducted at temperatures ranging from 700 to 900/sup 0/C. These processes usually employ a molten salt or salt eutectic as a heat sink and/or reaction medium. Salts for these operations were selected early in the development cycle. The selection criteria are being reevaluated. In this article we describe the processes now in use at Los Alamos and our studies of alternate salts and eutectics.

Bowersox, D.F.; Christensen, D.C.; Williams, J.D.

1987-01-01

327

PLUTONIUM-238 PRODUCTION TARGET DESIGN STUDIES  

SciTech Connect

A new supply chain is planned for plutonium-238 using existing reactors at the Oak Ridge National Laboratory (ORNL) and Idaho National Laboratory (INL) and existing chemical recovery facilities at ORNL. Validation and testing activities for new irradiation target designs have been conducted in three phases over a 2 year period to provide data for scale-up to production. Target design, qualification, target fabrication, and irradiation of fully-loaded targets have been accomplished. Data from post-irradiation examination (PIE) supports safety analysis and irradiation of future target designs.

Hurt, Christopher J [ORNL; Wham, Robert M [ORNL; Hobbs, Randall W [ORNL; Owens, R Steven [ORNL; Chandler, David [ORNL; Freels, James D [ORNL; Maldonado, G Ivan [ORNL

2014-01-01

328

Americium characterization by X-ray fluorescence and absorption spectroscopy in plutonium uranium mixed oxide  

NASA Astrophysics Data System (ADS)

Plutonium uranium mixed oxide (MOX) fuels are currently used in nuclear reactors. The actinides in these fuels need to be analyzed after irradiation for assessing their behaviour with regard to their environment and the coolant. In this work the study of the atomic structure and next-neighbour environment of Am in the (Pu,U)O2 lattice in an irradiated (60 MW d kg-1) MOX sample was performed employing micro-X-ray fluorescence (µ-XRF) and micro-X-ray absorption fine structure (µ-XAFS) spectroscopy. The chemical bonds, valences and stoichiometry of Am (˜0.66 wt%) are determined from the experimental data gained for the irradiated fuel material examined in its peripheral zone (rim) of the fuel. In the irradiated sample Am builds up as Am3+ species within an [AmO8]13- coordination environment (e.g. >90%) and no (<10%) Am(IV) or (V) can be detected in the rim zone. The occurrence of americium dioxide is avoided by the redox buffering activity of the uranium dioxide matrix.

Degueldre, Claude; Cozzo, Cedric; Martin, Matthias; Grolimund, Daniel; Mieszczynski, Cyprian

2013-06-01

329

Thermal Stability Studies of Candidate Decontamination Agents for Hanford’s Plutonium Finishing Plant Plutonium-Contaminated Gloveboxes  

SciTech Connect

This report provides the results of PNNL's and Fluor's studies of the thermal stabilities of potential wastes arising from decontamination of Hanford's Plutonium Finishing Plant's plutonium contaminated gloveboxes. The candidate wastes arising from the decontamination technologies ceric nitrate/nitric acid, RadPro, Glygel, and Aspigel.

Scheele, Randall D.; Cooper, Thurman D.; Jones, Susan A.; Ewalt, John R.; Compton, James A.; Trent, Donald S.; Edwards, Matthew K.; Kozelisky, Anne E.; Scott, Paul A.; Minette, Michael J.

2005-09-29

330

Uranium dioxide electrolysis  

DOEpatents

This is a single stage process for treating spent nuclear fuel from light water reactors. The spent nuclear fuel, uranium oxide, UO.sub.2, is added to a solution of UCl.sub.4 dissolved in molten LiCl. A carbon anode and a metallic cathode is positioned in the molten salt bath. A power source is connected to the electrodes and a voltage greater than or equal to 1.3 volts is applied to the bath. At the anode, the carbon is oxidized to form carbon dioxide and uranium chloride. At the cathode, uranium is electroplated. The uranium chloride at the cathode reacts with more uranium oxide to continue the reaction. The process may also be used with other transuranic oxides and rare earth metal oxides.

Willit, James L. (Batavia, IL); Ackerman, John P. (Prescott, AZ); Williamson, Mark A. (Naperville, IL)

2009-12-29

331

Sampling Carbon Dioxide  

NSDL National Science Digital Library

In this lab activity, student teams hypothesize which source has a greater becomes CO² concentration: their breath, auto exhaust, or air in the classroom. They test gas samples from each of these sources, plot data, and hypothesize about the respective role engine exhaust and animal respiration play in contemporary climate change. The lab procedures require Bromthymol Blue indicator solution (BTB), household ammonia, vinegar, and balloons. Links to videos supporting the investigations are provided. This activity is supported by a textbook chapter, "How is Carbon Dioxide Measured?," part of the unit, Climate Change, in Global Systems Science (GSS), an interdisciplinary course for high school students that emphasizes how scientists from a wide variety of fields work together to understand significant problems of global impact.

2012-09-28

332

Carbon Dioxide Landscape  

NASA Technical Reports Server (NTRS)

7 July 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a mid-summer view of the south polar residual cap at full MOC resolution, 1.5 m (5 ft) per pixel. During each of the three summers since the start of the MGS mapping mission in March 1999, the scarps that form mesas and pits in the 'Swiss cheese'-like south polar terrain have retreated an average of about 3 meters (1 yard). The material is frozen carbon dioxide; another 3 meters or so of each scarp is expected to be removed during the next summer, in late 2005. This image is located near 86.0oS, 350.8oW, and covers an area about 1.5 km (0.9 mi) wide. Sunlight illuminates the scene from the top/upper left.

2004-01-01

333

AMS of the Minor Plutonium Isotopes  

NASA Astrophysics Data System (ADS)

VERA, the Vienna Environmental Research Accelerator, is especially equipped for the measurement of actinides, and performs a growing number of measurements on environmental samples. While AMS is not the optimum method for each particular plutonium isotope, the possibility to measure 239Pu, 240Pu, 241Pu, 242Pu and 244Pu on the same AMS sputter target is a great simplification. We have obtained a first result on the global fallout value of 244Pu/239Pu = (5.7 ± 1.0) × 10-5 based on soil samples from Salzburg prefecture, Austria. Furthermore, we suggest using the 242Pu/240Pu ratio as an estimate of the initial 241Pu/239Pu ratio, which allows dating of the time of irradiation based solely on Pu isotopes. We have checked the validity of this estimate using literature data, simulations, and environmental samples from soil from the Salzburg prefecture (Austria), from the shut down Garigliano Nuclear Power Plant (Sessa Aurunca, Italy) and from the Irish Sea near the Sellafield nuclear facility. The maximum deviation of the estimated dates from the expected ages is 6 years, while relative dating of material from the same source seems to be possible with a precision of less than 2 years. Additional information carried by the minor plutonium isotopes may allow further improvements of the precision of the method.

Steier, P.; Hrnecek, E.; Priller, A.; Quinto, F.; Srncik, M.; Wallner, A.; Wallner, G.; Winkler, S.

2013-01-01

334

Measurements of plutonium residues from recovery processes  

SciTech Connect

Conventional methods of nondestructive assay (NDA) have accurately assayed the plutonium content of many forms of relatively pure and homogeneous bulk items. However, physical and chemical heterogeneities and the high and variable impurity levels of many categories of processing scrap bias the conventional NDA results. The materials also present a significant challenge to the assignment of reference values to process materials for purposes of evaluating the NDA methods. A recent study using impure, heterogeneous, pyrochemical residues from americium molten salt extraction (MSE) has been aimed at evaluating NDA assay methods based on conventional gamma-ray and neutron measurement techniques and enhanced with analyses designed to address the problems of heterogeneities and impurities. The study included a significant effort to obtain reference values for the MSE spent salts used in the study. Two of the improved NDA techniques, suitable for in-line assay of plutonium in bulk, show promise for timely in-process assays for one of the most difficult pyrochemical residues generated as well as for other impure heterogeneous scrap categories. 12 refs., 4 figs., 5 tabs.

Hsue, S.-T.; Langner, D.G.; Longmire, V.L.; Menlove, H.O.; Russo, P.A.; Sprinkle, J.K. Jr.

1989-01-01

335

Management of disused plutonium sealed sources  

SciTech Connect

The Global Threat Reduction Initiative's (GTRI) Offsite Source Recovery Project (OSRP) has been recovering excess and unwanted radioactive sealed sources since 1999, including more than 2,400 Plutonium (Pu)-238 sealed sources and 653 Pu-239-bearing sources that represent more than 10% of the total sources recovered by GTRI/OSRP to date. These sources have been recovered from hundreds of sites within the United States (US) and around the world. OSRP grew out of early efforts at the Los Alamos National Laboratory (LANL) to recover and disposition excess Plutonium-239 (Pu-239) sealed sources that were distributed in the 1960s and 1970s under the Atoms for Peace Program, a loan-lease program that serviced 31 countries, as well as domestic users. In the conduct of these recovery operations, GTRI/OSRP has been required to solve problems related to knowledge-of-inventory, packaging and transportation of fissile and heat-source materials, transfer of ownership, storage of special nuclear material (SNM) both at US Department of Energy (DOE) facilities and commercially, and disposal. Unique issues associated with repatriation from foreign countries, including end user agreements required by some European countries and denials of shipment, will also be discussed.

Whitworth, Julia Rose [Los Alamos National Laboratory; Pearson, Michael W [Los Alamos National Laboratory; Abeyta, Cristy [Los Alamos National Laboratory

2010-01-01

336

Co-Design: Fabrication of Unalloyed Plutonium  

SciTech Connect

The successful induction casting of plutonium is a challenge which requires technical expertise in areas including physical metallurgy, surface and corrosion chemistry, materials science, electromagnetic engineering and a host of other technologies all which must be applied in concert. Here at LANL, we are employing a combined experimental and computational approach to design molds and develop process parameters needed to produce desired temperature profiles and improved castings. Computer simulations are performed using the commercial code FLOW-3D and the LANL ASC computer code TRUCHAS to reproduce the entire casting process starting with electromagnetic or radiative heating of the mold and metal and continuing through pouring with coupled fluid flow, heat transfer and non-isothermal solidification. This approach greatly reduces the time required to develop a new casting designs and also increases our understanding of the casting process, leading to a more homogeneous, consistent product and better process control. We will discuss recent casting development results in support of unalloyed plutonium rods for mechanical testing.

Korzekwa, Deniece R. [Los Alamos National Laboratory; Knapp, Cameron M. [Los Alamos National Laboratory; Korzekwa, David A. [Los Alamos National Laboratory; Gibbs, John W [Northwestern University

2012-07-25

337

Avoided valence transition in a plutonium superconductor.  

PubMed

The d and f electrons in correlated metals are often neither fully localized around their host nuclei nor fully itinerant. This localized/itinerant duality underlies the correlated electronic states of the high-[Formula: see text] cuprate superconductors and the heavy-fermion intermetallics and is nowhere more apparent than in the [Formula: see text] valence electrons of plutonium. Here, we report the full set of symmetry-resolved elastic moduli of PuCoGa5-the highest [Formula: see text] superconductor of the heavy fermions ([Formula: see text] = 18.5 K)-and find that the bulk modulus softens anomalously over a wide range in temperature above [Formula: see text]. The elastic symmetry channel in which this softening occurs is characteristic of a valence instability-therefore, we identify the elastic softening with fluctuations of the plutonium 5f mixed-valence state. These valence fluctuations disappear when the superconducting gap opens at [Formula: see text], suggesting that electrons near the Fermi surface play an essential role in the mixed-valence physics of this system and that PuCoGa5 avoids a valence transition by entering the superconducting state. The lack of magnetism in PuCoGa5 has made it difficult to reconcile with most other heavy-fermion superconductors, where superconductivity is generally believed to be mediated by magnetic fluctuations. Our observations suggest that valence fluctuations play a critical role in the unusually high [Formula: see text] of PuCoGa5. PMID:25737548

Ramshaw, B J; Shekhter, Arkady; McDonald, Ross D; Betts, Jon B; Mitchell, J N; Tobash, P H; Mielke, C H; Bauer, E D; Migliori, Albert

2015-03-17

338

Expected radiation effects in plutonium immobilization ceramic  

SciTech Connect

The current formulation of the candidate ceramic for plutonium immobilization consists primarily of pyrochlore, with smaller amounts of hafnium-zirconolite, rutile, and brannerite or perovskite. At a plutonium loading of 10.5 weight %, this ceramic would be made metamict (amorphous) by radiation damage resulting from alpha decay in a time much less than 10,000 years, the actual time depending on the repository temperature as a function of time. Based on previous experimental radiation damage work by others, it seems clear that this process would also result in a bulk volume increase (swelling) of about 6% for ceramic that was mechanically unconfined. For the candidate ceramic, which is made by cold pressing and sintering and has porosity amounting to somewhat more than this amount, it seems likely that this swelling would be accommodated by filling in the porosity, if the material were tightly confined mechanically by the waste package. Some ceramics have been observed to undergo microcracking as a result of radiation-induced anisotropic or differential swelling. It is unlikely that the candidate ceramic will microcrack extensively, for three reasons: (1) its phase composition is dominated by a single matrix mineral phase, pyrochlore, which has a cubic crystal structure and is thus not subject to anisotropic swelling; (2) the proportion of minor phases is small, minimizing potential cracking due to differential swelling; and (3) there is some flexibility in sintering process parameters that will allow limitation of the grain size, which can further limit stresses resulting from either cause.

Van Konynenburg, R.A., LLNL

1997-09-01

339

Solvent extraction system for plutonium colloids and other oxide nano-particles  

SciTech Connect

The invention provides a method for extracting plutonium from spent nuclear fuel, the method comprising supplying plutonium in a first aqueous phase; contacting the plutonium aqueous phase with a mixture of a dielectric and a moiety having a first acidity so as to allow the plutonium to substantially extract into the mixture; and contacting the extracted plutonium with second a aqueous phase, wherein the second aqueous phase has a second acidity higher than the first acidity, so as to allow the extracted plutonium to extract into the second aqueous phase. The invented method facilitates isolation of plutonium polymer without the formation of crud or unwanted emulsions.

Soderholm, Lynda; Wilson, Richard E; Chiarizia, Renato; Skanthakumar, Suntharalingam

2014-06-03

340

Plutonium contamination in the environment. September 1977-November 1989 (A Bibliography from the Selected Water Resources Abstracts data base). Report for September 1977-November 1989  

SciTech Connect

This bibliography contains citations concerning the ecological impact of plutonium contamination in the environment. Topics include plutonium contamination in freshwater and marine sediments, plutonium bioaccumulation, plutonium transport in the food chain, plutonium contamination bioindicators, methods of analysis, plutonium genotoxicity, plutonium contamination in soil and groundwater, and plutonium contamination from nuclear fallout and nuclear facilities. Plutonium distribution changes due to stratification in oxic and anoxic environments are described. (Contains 83 citations fully indexed and including a title list.)

Not Available

1990-05-01

341

Estimation of plutonium in Hanford Site waste tanks based on historical records  

SciTech Connect

An estimation of plutonium in the Hanford Site waste storage tanks is important to nuclear criticality concerns. A reasonable approach for estimating the plutonium in the tanks can be established by considering the recovery efficiency of the chemical separation plants on the plutonium produced in the Hanford reactors. The waste loss from the separation processes represents the bulk of the plutonium in the waste tanks. The lesser contributor of plutonium to the waste tanks was the Plutonium Finishing Plant (PFP). When the PFP waste is added to the plutonium waste from separations, the result is the total estimated amount of plutonium discharged to the waste tanks at the Hanford Site. This estimate is for criticality concerns, and therefore is based on conservative assumptions (giving higher plutonium values). The estimate has been calculated to be {approx}981 kg of plutonium in the single- and double-shell high-level waste tanks.

Roetman, V.E.; Roblyer, S.P.; Toffer, H.

1994-09-01

342

Carbon Dioxide Sequestration Industrial-scale processes are available for separating carbon dioxide from the post-  

E-print Network

Carbon Dioxide Sequestration Industrial-scale processes are available for separating carbon dioxide of a coal gasification power plant. The separated carbon dioxide can be compressed and transported dioxide separation and sequestration because the lower cost of carbon dioxide separation from

343

Plutonium recovery from spent reactor fuel by uranium displacement  

DOEpatents

A process for separating uranium values and transuranic values from fission products containing rare earth values when the values are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is reestablished.

Ackerman, John P. (Downers Grove, IL)

1992-01-01

344

Plutonium recovery from spent reactor fuel by uranium displacement  

DOEpatents

A process is described for separating uranium values and transuranic values from fission products containing rare earth values when the values are contained together in a molten chloride salt electrolyte. A molten chloride salt electrolyte with a first ratio of plutonium chloride to uranium chloride is contacted with both a solid cathode and an anode having values of uranium and fission products including plutonium. A voltage is applied across the anode and cathode electrolytically to transfer uranium and plutonium from the anode to the electrolyte while uranium values in the electrolyte electrolytically deposit as uranium metal on the solid cathode in an amount equal to the uranium and plutonium transferred from the anode causing the electrolyte to have a second ratio of plutonium chloride to uranium chloride. Then the solid cathode with the uranium metal deposited thereon is removed and molten cadmium having uranium dissolved therein is brought into contact with the electrolyte resulting in chemical transfer of plutonium values from the electrolyte to the molten cadmium and transfer of uranium values from the molten cadmium to the electrolyte until the first ratio of plutonium chloride to uranium chloride is reestablished.

Ackerman, J.P.

1992-03-17

345

The mysterious world of plutonium metallurgy: Past and future  

SciTech Connect

The first atomic bomb detonated at the Trinity Site in New Mexico on July 16, 1945, used plutonium, a man-made element discovered < 5 yr earlier. The story of how Manhattan Project scientists and engineers tackled the mysteries of this element and fabricated it into the first atomic bomb is one of the most fascinating in the history of metallurgy and materials. The authors are currently trying to generate renewed interest in plutonium metallurgy because of the challenge posed by President Clinton, i.e., to keep the nuclear stockpile of weapons safe and reliable without nuclear testing. The stockpile stewardship challenge requires either a lifetime extension of the plutonium components or a remanufacture--neither of which can be verified by testing. In turn, this requires that one achieve a better fundamental understanding of plutonium. Of special interest is the effect of self-irradiation on the properties and on the long-term stability of plutonium and its alloys. Additional challenges arise from long-term concerns about disposing of plutonium and dealing with its environmental legacy. It is imperative to interest the next generation of students in these plutonium challenges.

Hecker, S.S.; Hammel, E.F. [Los Alamos National Lab., NM (United States)

1998-12-31

346

Implementation impacts of PRL methodology. [PRL (Plutonium Recovery Limit)  

SciTech Connect

This report responds to a DOE-SR request to evaluate the impacts from implementation of the proposed Plutonium Recovery Limit (PRL) methodology. The PRL Methodology is based on cost minimization for decisions to discard or recover plutonium contained in scrap, residues, and other plutonium bearing materials. Implementation of the PRL methodology may result in decisions to declare as waste certain plutonium bearing materials originally considered to be a recoverable plutonium product. Such decisions may have regulatory impacts, because any material declared to be waste would immediately be subject to provisions of the Resource Conservation and Recovery Act (RCRA). The decision to discard these materials will have impacts on waste storage, treatment, and disposal facilities. Current plans for the de-inventory of plutonium processing facilities have identified certain materials as candidates for discard based upon the economic considerations associated with extending the operating schedules for recovery of the contained plutonium versus potential waste disposal costs. This report evaluates the impacts of discarding those materials as proposed by the F Area De-Inventory Plan and compares the De-Inventory Plan assessments with conclusions from application of the PRL. The impact analysis was performed for those materials proposed as potential candidates for discard by the De-Inventory Plan. The De-Inventory Plan identified 433 items, containing approximately 1% of the current SRS Pu-239 inventory, as not appropriate for recovery as the site moves to complete the mission of F-Canyon and FB-Line. The materials were entered into storage awaiting recovery as product under the Department's previous Economic Discard Limit (EDL) methodology which valued plutonium at its incremental cost of production in reactors. An application of Departmental PRLs to the subject 433 items revealed that approximately 40% of them would continue to be potentially recoverable as product plutonium.

Caudill, J.A.; Krupa, J.F.; Meadors, R.E.; Odum, J.V.; Rodrigues, G.C.

1993-02-01

347

Plutonium immobilization plant using glass in existing facilities at the Savannah River Site  

SciTech Connect

The Plutonium Immobilization Plant (PIP) accepts plutonium (Pu) from pit conversion and from non-pit sources and, through a glass immobilization process, converts the plutonium into an immobilized form that can be disposed of in a high level waste (HLW) repository. The objective is to make an immobilized form, suitable for geologic disposal, in which the plutonium is as inherently unattractive and inaccessible as the plutonium in spent fuel from commercial reactors.

DiSabatino, A., LLNL

1998-06-01

348

Om plutoniums giftighed Inden for de seneste mneder har sagen om  

E-print Network

1 Om plutoniums giftighed Inden for de seneste måneder har sagen om Thule-arbejderne nået sit plutonium-239, der blev spredt på isen ved flystyrtet. Plutonium og kræftsygdomme Plutonium er et stof, man tungt opløselig form. Da plutonium kun udsender alfa-stråling er det - set fra et helsefysisk synspunkt

349

Implication of p16 inactivation in tumorigenic activity of respiratory epithelial cell lines and adenocarcinoma cell line established from plutonium-induced lung tumor in rat  

Microsoft Academic Search

To investigate whether p16 inactivation is involved in the development of rat pulmonary tumors, we compared the p16 status and tumorigenicity of cell lines which indicated different p16 status. The tumor cell line (PuD2) was established from lung adenocarcinoma induced in plutonium dioxide-inhaled rat in this\\u000a study. The virus-immortalized SV40T2 cells, benzo[a]pyrene-induced BP cells, BP-derived BP(P)Tu cells, and gamma ray-transformed

Yutaka Yamada; Akifumi Nakata; Mitsuaki A. Yoshida; Yoshiya Shimada; Yoichi Oghiso; Jean-Luc Poncy

2010-01-01

350

NASA Satellite Sees Carbon Dioxide  

NSDL National Science Digital Library

In this problem set, learners will analyze a map of atmospheric carbon dioxide derived from satellite data. Answer key is provided. This is part of Earth Math: A Brief Mathematical Guide to Earth Science and Climate Change.

2012-08-03

351

Reducing carbon dioxide to products  

DOEpatents

A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

2014-09-30

352

Carbon Dioxide and Ocean Acidification  

NSDL National Science Digital Library

Demonstrates the affect of increased dissolved carbon dioxide on water pH using a cheap, non-toxic acid/base indicator. Students bubble breath through a straw into red cabbage juice and note the color change.

Chris Lewis

353

Decision model for evaluating reactor disposition of excess plutonium  

SciTech Connect

The US Department of Energy is currently considering a range of technologies for disposition of excess weapon plutonium. Use of plutonium fuel in fission reactors to generate spent fuel is one class of technology options. This report describes the inputs and results of decision analyses conducted to evaluate four evolutionary/advanced and three existing fission reactor designs for plutonium disposition. The evaluation incorporates multiple objectives or decision criteria, and accounts for uncertainty. The purpose of the study is to identify important and discriminating decision criteria, and to identify combinations of value judgments and assumptions that tend to favor one reactor design over another.

Edmunds, T.

1995-02-01

354

Accelerator-driven assembly for plutonium transformation (ADAPT)  

NASA Astrophysics Data System (ADS)

A particle accelerator-driven spallation target and corresponding blanket region are proposed for the ultimate disposition of weapons-grade plutonium being retired from excess nuclear weapons in the U.S. and Russia. The highly fissle plutonium is contained within .25 to .5 cm diameter silicon-carbide coated graphite beads, which are cooled by helium, within the slightly subcritical blanket region. Major advantages include very high one-pass burnup (over 90%), a high integrity waste form (the coated beads), and operation in a subcritical mode, thereby minimizing the vulnerability to the positive reativity feedbacks often associated with plutonium fuel.

Tuyle, Greorgy J. Van; Todosow, Michael; Powell, James; Schweitzer, Donald

1995-01-01

355

Amarillo National Resource Center for Plutonium 1999 plan  

SciTech Connect

The purpose of the Amarillo National Resource Center for Plutonium is to serve the Texas Panhandle, the State of Texas and the US Department of Energy by: conducting scientific and technical research; advising decision makers; and providing information on nuclear weapons materials and related environment, safety, health, and nonproliferation issues while building academic excellence in science and technology. This paper describes the electronic resource library which provides the national archives of technical, policy, historical, and educational information on plutonium. Research projects related to the following topics are described: Environmental restoration and protection; Safety and health; Waste management; Education; Training; Instrumentation development; Materials science; Plutonium processing and handling; and Storage.

NONE

1999-01-30

356

Determination of plutonium in air and smear samples  

SciTech Connect

A method has been developed for the determination of plutonium in air samples and smear samples that were collected on filter papers. The sample papers are digested in nitric acid, extracted into 2-thenoyltrifluoroacetone (TTA)-xylene, and evaporated onto stainless steel disks. Alpha spectrometry is employed to determine the activity of each plutonium isotope. Each sample is spiked with plutonium-236. All glassware used in the procedure is disposable. The detection limits are 3 and 5 dpm (disintegrations per minute) for air and smear samples, respectively, with an average recovery of 87%.

Hinton, Jr., E. R.; Tucker, W. O.

1981-02-27

357

Plutonium dissolution from Rocky Flats Plant incinerator ash  

SciTech Connect

Rockwell Hanford Operations (Rockwell) soon will commence recovery of plutonium from Rocky Flats Plant incinerator ash. In preparation for this processing, Rockwell undertook literature and laboratory studies to identify, select and optimize plutonium dissolution methods for treating the ash. Ash reburning, followed by dissolution in nitric acid containing calcium fluoride, was selected as the processing method for the ash. Recommended values of process parameters were identified. Using the selected process, 99.5% plutonium recovery was achieved, leaving about 12.7 wt % heel residue for an equal weight composite of the three ashes tested. 15 refs., 26 figs.

Delegard, C.H.

1985-06-01

358

Theory of Antineutrino Monitoring of Burning MOX Plutonium Fuels  

E-print Network

This letter presents the physics and feasibility of reactor antineutrino monitoring to verify the burnup of plutonium loaded in the reactor as a Mixed Oxide (MOX) fuel. It examines the magnitude and temporal variation in the antineutrino signals expected for different MOX fuels, for the purposes of nuclear accountability and safeguards. The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium. Thus, antineutrino monitoring could be used to verify the destruction of plutonium in reactors, though verifying the grade of the plutonium being burned is found to be more challenging.

Hayes, A C; Nieto, Michael Martin; WIlson, W B

2011-01-01

359

Theory of Antineutrino Monitoring of Burning MOX Plutonium Fuels  

E-print Network

This letter presents the physics and feasibility of reactor antineutrino monitoring to verify the burnup of plutonium loaded in the reactor as a Mixed Oxide (MOX) fuel. It examines the magnitude and temporal variation in the antineutrino signals expected for different MOX fuels, for the purposes of nuclear accountability and safeguards. The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium. Thus, antineutrino monitoring could be used to verify the destruction of plutonium in reactors, though verifying the grade of the plutonium being burned is found to be more challenging.

A. C. Hayes; H. R. Trellue; Michael Martin Nieto; W. B. WIlson

2011-10-03

360

Gas pycnometry for density determination of plutonium parts  

SciTech Connect

The traditional method for plutonium density determination is by measuring the weight loss of the component when it is immersed in a liquid of known density, Archimedes` Principle. The most commonly used heavy liquids that are compatible for plutonium measurement are freon and monobromobenzene, but these pose serious environmental and health hazards. The contaminated liquid is also a radiological waste concern with difficult disposition. A gaseous medium would eliminate these environmental and health concerns. A collaborative research effort between the Savannah River Technology Center and Los Alamos National Laboratory was undertaken to determine the feasibility of a gaseous density measurement process for plutonium hemishells.

Collins, S.; Randolph, H.W.

1997-08-19

361

Influence of void fraction on plutonium recycling in BWR  

NASA Astrophysics Data System (ADS)

The uncertainty of commercial operation of fast breeder reactors (FBR) claims for another solution to the plutonium produced in light water reactors (LWR). As one option, recently, the plutonium recycling in LWR becomes an important consideration. A study on the impact of changing void fraction on plutonium recycling in BWR has been performed. Two types of uranium sources in mixed oxide (MOX) fuel, namely the depleted uranium and the natural uranium have been evaluated. The trend is similar for both MOX fuels that BWR can gain its critical condition for the void fraction of less than 42% and it may be operated in critical condition for the void fraction of 42% and 95%.

Surbakti, R.; Waris, A.; Basar, K.; Permana, S.; Kurniadi, R.

2012-06-01

362

Strategies for denaturing the weapons-grade plutonium stockpile  

SciTech Connect

In the next few years, approximately 50 metric tons of weapons-grade plutonium and 150 metric tons of highly-enriched uranium (HEU) may be removed from nuclear weapons in the US and declared excess. These materials represent a significant energy resource that could substantially contribute to our national energy requirements. HEU can be used as fuel in naval reactors, or diluted with depleted uranium for use as fuel in commercial reactors. This paper proposes to use the weapons-grade plutonium as fuel in light water reactors. The first such reactor would demonstrate the dual objectives of producing electrical power and denaturing the plutonium to prevent use in nuclear weapons.

Buckner, M.R.; Parks, P.B.

1992-10-01

363

Recuperative supercritical carbon dioxide cycle  

DOEpatents

A power plant includes a closed loop, supercritical carbon dioxide system (CLS-CO.sub.2 system). The CLS-CO.sub.2 system includes a turbine-generator and a high temperature recuperator (HTR) that is arranged to receive expanded carbon dioxide from the turbine-generator. The HTR includes a plurality of heat exchangers that define respective heat exchange areas. At least two of the heat exchangers have different heat exchange areas.

Sonwane, Chandrashekhar; Sprouse, Kenneth M; Subbaraman, Ganesan; O'Connor, George M; Johnson, Gregory A

2014-11-18

364

System for reducing sulfur dioxide  

SciTech Connect

A system for reducing sulfur dioxide in which a vessel is provided with an inlet for receiving coal and a plurality of gas distribution nozzles for receiving the sulfur dioxide and discharging same downwardly in the lower portion of the vessel for flowing upwardly in a counterflow relation to the coal. The coal flows through a distribution device located in the hopper section of the vessel for insuring an even distribution of coal through the vessel.

Bischoff, W.F.; Steiner, P.

1980-06-10

365

Measurements of impure reactor-grade plutonium using the increase in totals neutrons from plutonium-241 decay  

NASA Astrophysics Data System (ADS)

We have developed a new technique to obtain accurate measurements of impure plutonium mass using neutron counting. The technique is based on making two or more totals neutron measurements with a time separation that is long enough to measure the decay of 241Pu ( T1/2=14.7 y) to 241Am. Because of the excellent precision for totals neutron counting, short measurement intervals are adequate and time separations as short as a few months can give useful results. The known change of the plutonium isotopics with time can be used to calculate the alpha value [( ?, n) to spontaneous fission ratio]. The alpha value can be accurately calculated for pure oxide samples; however, for impure samples, the alpha value must be determined from a measurement such as multiplicity counting or the totals neutron counting in the present technique. For bulk samples with significant neutron multiplication, the neutron coincidence (doubles) count is needed to calculate the 240Pu-effective mass. However, for waste samples such as 200-l drums or other very dilute plutonium loadings, the multiplication is unity and the plutonium mass can be calculated directly from the two totals counts without the requirement for coincidence counting. For many present and future applications of reactor-grade plutonium verification, impure plutonium is in a storage condition as opposed to active chemical processing. In these storage conditions, the plutonium samples routinely receive repeat measurements over time for the purposes of accountability and international inspection. This storage of plutonium facilitates the present dual measurement approach. This paper gives the concept of the new technique as well as an evaluation of the accuracy for different types of plutonium.

Menlove, H. O.; Wenz, T. R.

1999-03-01

366

Bayesian methods for interpreting plutonium urinalysis data  

SciTech Connect

The authors discuss an internal dosimetry problem, where measurements of plutonium in urine are used to calculate radiation doses. The authors have developed an algorithm using the MAXENT method. The method gives reasonable results, however the role of the entropy prior distribution is to effectively fit the urine data using intakes occurring close in time to each measured urine result, which is unrealistic. A better approximation for the actual prior is the log-normal distribution; however, with the log-normal distribution another calculational approach must be used. Instead of calculating the most probable values, they turn to calculating expectation values directly from the posterior probability, which is feasible for a small number of intakes.

Miller, G.; Inkret, W.C.

1995-09-01

367

Development of a plutonium-239 recovery incinerator  

SciTech Connect

A Plutonium-239 Recovery Incinerator is being developed for the Savannah River Plant (SRP) to reduce the volume of solid glovebox waste and to allow recovery of Pu-239 from the waste. The process will also allow treatment of some waste materials that are not certifiable for disposal at the Waste Isolation Pilot Plant (WIPP). It will consist of two electrically heated combustion chambers (furnace and afterburner) and a dry filtration off-gas system. A unique feature of the process is that it uses pyrohydrolysis to produce an ash that is amenable to Pu recovery through nitric acid/HF dissolution. A series of thermogravimetric (TGA) analyses have been performed to characterize potential incinerator feed materials. A functioning furnace mockup was built and operated to demonstrate electrically-heated pyrohydrolysis operation. 8 refs., 4 figs.

Williams, S; Charlesworth, D L

1988-01-01

368

Uranium and plutonium isotopes in the atmosphere  

SciTech Connect

Uranium 234 and 235 were found to be highly enriched relative to uranium 238 in several rain samples collected at Fayetteville, Arkansas, during the months of April and May 1980. The anomalous uranium appears to have originated from the Soviet satellite Cosmos-954, which fell over Canada on January 24, 1978. The uranium fallout occurred just about the time Mount St. Helens erupted on May 18, 1980. The concentration of /sup 238/U in rain increased markedly after the eruption of Mount St. Helens, and it appeared as if a large quantity of natural uranium was injected into the atmosphere by the volcanic eruption. The pattern of variation of the concentrations of uranium in rain after the eruption of Mount St. Helens was found to be similar to that of plutonium isotopes.

Sakuragi, Y.; Meason, J.L.; Kuroda, P.K.

1983-04-20

369

Crashworthy sealed pressure vessel for plutonium transport  

SciTech Connect

A rugged transportation package for the air shipment of radioisotopic materials was recently developed. This package includes a tough, sealed, stainless steel inner containment vessel of 1460 cc capacity. This vessel, intended for a mass load of up to 2 Kg PuO/sub 2/ in various isotopic forms (not to exceed 25 watts thermal activity), has a positive closure design consisting of a recessed, shouldered lid fastened to the vessel body by twelve stainless-steel bolts; sealing is accomplished by a ductile copper gasket in conjunction with knife-edge sealing beads on both the body and lid. Follow-on applications of this seal in newer, smaller packages for international air shipments of plutonium safeguards samples, and in newer, more optimized packages for greater payload and improved efficiency and utility, are briefly presented.

Andersen, J.A.

1980-01-01

370

Thermophysical properties of coexistent phases of plutonium  

SciTech Connect

Plutonium is the element with the greatest number of allotropic phases. Thermally induced transformations between these phases are typically characterized by thermal hysteresis and incomplete phase reversion. With Ga substitutal in the lattice, low symmetry phases are replaced by a higher symmetry phase. However, the low temperature Martensitic phase transformation ({delta} {yields} {alpha}{prime}) in Ga stabilized {delta}-phase Pu is characterized by a region of thermal hysteresis which can reach 200 C in extent. These regions of thermal hysteresis offer a unique opportunity to study thermodynamics in inhomogeneous systems of coexistent phases. The results of thermophysical properties measured for samples of inhomogeneous unalloyed and Ga alloyed Pu will be discussed and compared with similar measurements of their single phase constituents.

Freibert, Franz J [Los Alamos National Laboratory; Mitchell, Jeremy N [Los Alamos National Laboratory; Saleh, Tarik A [Los Alamos National Laboratory; Schwartz, Dan S [Los Alamos National Laboratory

2009-01-01

371

Global plutonium management: A security option  

SciTech Connect

The US surplus plutonium disposition program was created to reduce the proliferation risk posed by the fissile material from thousands of retired nuclear weapons. The Department of Energy has decided to process its Put into a form as secure as Pu in civilian spent fuel. While implementation issues have been considered, a major one (Russian reciprocity) remains unresolved. Russia has made disposition action conditional on extracting the fuel value of its Pu but lacks the infrastructure to do so. Assistance in the construction of the required facilities would conflict with official US policy opposing the development of a Pu fuel cycle. The resulting stagnation provides impetus for a reevaluation of US nonproliferation objectives and Pu disposition options. A strategy for satisfying Russian fuel value concerns and reducing the proliferation risk posed by surplus weapons-grade plutonium (WGPu) is proposed. The effectiveness of material alteration (e.g., isotopic, chemical, etc.{hor_ellipsis}) at reducing the desire, ability and opportunity for proliferation is assessed. Virtually all the security benefits attainable by material processing can be obtained by immobilizing Pu in large unit size/mass monoliths without a radiation barrier. Russia would be allowed to extract the Pu at a future date for use as fuel in a verifiable manner. Remote tracking capability, if proven feasible, would further improve safeguarding capability. As an alternate approach, the US could compensate Russia for its Pu, allowing it to be disposed of or processed elsewhere. A market based method for pricing Pu is proposed. Surplus Pu could represent access to nuclear fuel at a fixed price at a future date. This position can be replicated in the uranium market and priced using derivative theory. The proposed strategy attempts to meet nonproliferation objectives by recognizing technical limitations and satisfying political constraints.

Sylvester, K.W.B.

1998-12-31

372

ARRAYS OF BOTTLES OF PLUTONIUM NITRATE SOLUTION  

SciTech Connect

In October and November of 1981 thirteen approaches-to-critical were performed on a remote split table machine (RSTM) in the Critical Mass Laboratory of Pacific Northwest Laboratory (PNL) in Richland, Washington using planar arrays of polyethylene bottles filled with plutonium (Pu) nitrate solution. Arrays of up to sixteen bottles were used to measure the critical number of bottles and critical array spacing with a tight fitting Plexiglas® reflector on all sides of the arrays except the top. Some experiments used Plexiglas shells fitted around each bottles to determine the effect of moderation on criticality. Each bottle contained approximately 2.4 L of Pu(NO3)4 solution with a Pu content of 105 g Pu/L and a free acid molarity H+ of 5.1. The plutonium was of low 240Pu (2.9 wt.%) content. These experiments were sponsored by Rockwell Hanford Operations because of the lack of experimental data on the criticality of arrays of bottles of Pu solution such as might be found in storage and handling at the Purex Facility at Hanford. The results of these experiments were used “to provide benchmark data to validate calculational codes used in criticality safety assessments of [the] plant configurations” (Ref. 1). Data for this evaluation were collected from the published report (Ref. 1), the approach to critical logbook, the experimenter’s logbook, and communication with the primary experimenter, B. Michael Durst. Of the 13 experiments preformed 10 were evaluated. One of the experiments was not evaluated because it had been thrown out by the experimenter, one was not evaluated because it was a repeat of another experiment and the third was not evaluated because it reported the critical number of bottles as being greater than 25. Seven of the thirteen evaluated experiments were determined to be acceptable benchmark experiments. A similar experiment using uranyl nitrate was benchmarked as U233-SOL-THERM-014.

Margaret A. Marshall

2012-09-01

373

Solubility of plutonium and waste evaporation  

SciTech Connect

Chemical processing of irradiated reactor elements at the Savannah River Site separates uranium, plutonium and fission products; fission products and process-added chemicals are mixed with an excess of NaOH and discharged as a basic slurry into large underground tanks for temporary storage. The slurry is composed of base-insoluble solids that settle to the bottom of the tank; the liquid supemate contains a mixture of base-soluble chemicals--nitrates, nitrites aluminate, sulfate, etc. To conserve space in the waste tanks, the supemate is concentrated by evaporation. As the evaporation proceeds, the solubilities of some components are exceeded, and these species crystallize from solution. Normally, these components are soluble in the hot solution discharged from the waste tank evaporator and do not crystallize until the solution cools. However, concern was aroused at West Valley over the possibility that plutonium would precipitate and accumulate in the evaporator, conceivably to the point that a nuclear accident was possible. There is also a concern at SRS from evaporation of sludge washes, which arise from washing the base-insoluble solids ({open_quote}sludge{close_quote}) with ca. 1M NaOH to reduce the Al and S0{sub 4}{sup {minus}2} content. The sludge washes of necessity extract a low level of Pu from the sludge and are evaporated to reduce their volume, presenting the possibility of precipitating Pu. Measurements of the solubility of Pu in synthetic solutions of similar composition to waste supernate and sludge washes are described in this report.

Karraker, D.G.

1993-10-22

374

Development of the Direct Fabrication Process for Plutonium Immobilization  

SciTech Connect

The current baseline process for fabricating pucks for the Plutonium Immobilization Program includes granulation of the milled feed prior to compaction. A direct fabrication process was demonstrated that eliminates the need for granulation.

Congdon, J.W.

2001-07-10

375

Overview of Modeling and Simulations of Plutonium Aging  

SciTech Connect

Computer-aided materials research is now an integral part of science and technology. It becomes particularly valuable when comprehensive experimental investigations and materials testing are too costly, hazardous, or of excessive duration; then, theoretical and computational studies can supplement and enhance the information gained from limited experimental data. Such is the case for improving our fundamental understanding of the properties of aging plutonium in the nuclear weapons stockpile. The question of the effects of plutonium aging on the safety, security, and reliability of the nuclear weapons stockpile emerged after the United States closed its plutonium manufacturing facility in 1989 and decided to suspend any further underground testing of nuclear weapons in 1992. To address this, the Department of Energy's National Nuclear Security Administration (NNSA) initiated a research program to investigate plutonium aging, i.e., the changes with time of properties of Pu-Ga alloys employed in the nuclear weapons and to develop models describing these changes sufficiently reliable to forecast them for several decades. The November 26, 2006 press release by the NNSA summarizes the conclusions of the investigation, '...there appear to be no serious or sudden changes occurring, or expected to occur, in plutonium that would affect performance of pits beyond the well-understood, gradual degradation of plutonium materials'. Furthermore, 'These studies show that the degradation of plutonium in our nuclear weapons will not affect warhead reliability for decades', then NNSA Administrator Linton Brooks said. 'It is now clear that although plutonium aging contributes, other factors control the overall life expectancy of nuclear weapons systems'. The origin of plutonium aging is the natural decay of certain plutonium isotopes. Specifically, it is the process of alpha decay in which a plutonium atom spontaneously splits into a 5 MeV alpha particle and an 85keV uranium recoil. The alpha particle traverses the lattice, slowly loosing energy through electronic excitations, acquiring two electrons to become a helium atom, then finally coming to rest approximately 10 microns away with the generation of a few-hundred Frenkel pairs. The uranium recoil immediately displaces a couple-thousand Pu atoms from their original lattice sites. This process, which occurs at a rate of approximately 41 parts-per-million per year, is the source of potential property changes in aging plutonium. Plutonium aging encompasses many areas of research: radiation damage and radiation effects, diffusion of point defects, impurities and alloying elements, solid state phase transformations, dislocation dynamics and mechanical properties, equations of state under extreme pressures, as well as surface oxidation and corrosion. Theory, modeling, and computer simulations are involved to various degrees in many of these areas. The joint research program carried out at Lawrence Livermore National Laboratory and Los Alamos National Laboratory encompassed experimental measurements of numerous properties of newly fabricated reference alloys, archival material that have accumulated the effects of several decades of radioactive decay, and accelerated aging alloys in which the isotropic composition was adjusted to increase the rate of self-irradiation damage. In particular, the physical and chemical processes of nuclear materials degradation were to be studied individually and in great depth. Closely coupled to the experimental efforts are theory, modeling, and simulations. These efforts, validated by the experiments, aim to develop predictive models to evaluate the effects of age on the properties of plutonium. The need to obtain a scientific understanding of plutonium aging has revitalized fundamental research on actinides and plutonium in particular. For example, the experimental discovery of superconductivity in Pu-based compounds, the observation of helium bubbles in naturally aged material, and the measurement of phonon dispersion properties in gallium-stabilized delta plu

Schwartz, A J; Wolfer, W G

2007-04-24

376

Plutonium recovery at the Los Alamos Scientific Laboratory  

SciTech Connect

Research programs have led to the adoption of procedures for all phases of plutonium recovery and purification. This report discusses some of the many procedures required to recover and purify the plutonium contained in the residues generated by LASL research, process development, and production activities. The report also discusses general plant facilities, the liquid and gaseous effluents, and solid waste management practices at the New Plutonium Facility, TA-55. Many of the processes or operations are merely steps in preparing the feed for one of the purification systems. For example, the plutonium is currently removed from noncombustibles in the pickling operation with an HNO/sub 3/ leach. The HNO/sub 3/ leach solution is the product of this operation and is sent to one of the nitrate anion-exchange systems for concentration and purification.

Christensen, E.L.

1980-06-01

377

PRESSURIZATION OF CONTAINMENT VESSELS FROM PLUTONIUM OXIDE CONTENTS  

SciTech Connect

Transportation and storage of plutonium oxide is typically done using a convenience container to hold the oxide powder which is then placed inside a containment vessel. Intermediate containers which act as uncredited confinement barriers may also be used. The containment vessel is subject to an internal pressure due to several sources including; (1) plutonium oxide provides a heat source which raises the temperature of the gas space, (2) helium generation due to alpha decay of the plutonium, (3) hydrogen generation due to radiolysis of the water which has been adsorbed onto the plutonium oxide, and (4) degradation of plastic bags which may be used to bag out the convenience can from a glove box. The contributions of these sources are evaluated in a reasonably conservative manner.

Hensel, S.

2012-03-27

378

Plutonium and Americium Geochemistry at Hanford: A Site Wide Review  

SciTech Connect

This report was produced to provide a systematic review of the state-of-knowledge of plutonium and americium geochemistry at the Hanford Site. The report integrates existing knowledge of the subsurface migration behavior of plutonium and americium at the Hanford Site with available information in the scientific literature regarding the geochemistry of plutonium and americium in systems that are environmentally relevant to the Hanford Site. As a part of the report, key research needs are identified and prioritized, with the ultimate goal of developing a science-based capability to quantitatively assess risk at sites contaminated with plutonium and americium at the Hanford Site and the impact of remediation technologies and closure strategies.

Cantrell, Kirk J.; Felmy, Andrew R.

2012-08-23

379

Crystalline ceramics: Waste forms for the disposal of weapons plutonium  

SciTech Connect

At present, there are three seriously considered options for the disposition of excess weapons plutonium: (i) incorporation, partial burn-up and direct disposal of MOX-fuel; (ii) vitrification with defense waste and disposal as glass ``logs``; (iii) deep borehole disposal (National Academy of Sciences Report, 1994). The first two options provide a safeguard due to the high activity of fission products in the irradiated fuel and the defense waste. The latter option has only been examined in a preliminary manner, and the exact form of the plutonium has not been identified. In this paper, we review the potential for the immobilization of plutonium in highly durable crystalline ceramics apatite, pyrochlore, monazite and zircon. Based on available data, we propose zircon as the preferred crystalline ceramic for the permanent disposition of excess weapons plutonium.

Ewing, R.C.; Lutze, W. [New Mexico Univ., Albuquerque, NM (United States); Weber, W.J. [Pacific Northwest Lab., Richland, WA (United States)

1995-05-01

380

Analytical inverse model for post-event attribution of plutonium  

E-print Network

including simplified and realistic cases. For the simplistic cases, only two isotopes comprised the material being fissioned. In the realistic cases, both Weapons Grade and Reactor Grade plutonium were used to cover the spectrum of possible fissile material...

Miller, James Christopher

2009-05-15

381

Process for immobilizing plutonium into vitreous ceramic waste forms  

DOEpatents

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Feng, X.; Einziger, R.E.

1997-08-12

382

Sci-Tech Feature: Plutonium. Fuel for Controversy.  

ERIC Educational Resources Information Center

Despite opposition by environmental organizations, Japan plans to import plutonium from France and Great Britain. Interviews Toichi Sakata, director of the nuclear fuel division of the Science and Technology Agency, who explains why Japan needs the radioactive substance. (MDH)

Iikubo, Ryuko

1993-01-01

383

Radiation from plutonium 238 used in space applications  

NASA Technical Reports Server (NTRS)

The principal mode of the nuclear decay of plutonium 238 is by alpha particle emission at a rate of 17 curies per gram. Gamma radiation also present in nuclear fuels arises primarily from the nuclear de-excitation of daughter nuclei as a result of the alpha decay of plutonium 238 and reactor-produced impurities. Plutonium 238 has a spontaneous fission half life of 4.8 x 10 to the 10th power years. Neutrons associated with this spontaneous fission are emitted at a rate of 28,000 neutrons per second per gram. Since the space fuel form of plutonium 238 is the oxide pressed into a cermet with molybdenum, a contribution to the neutron emission rate arises from (alpha, n) reactions with 0-17 and 0-18 which occur in natural oxygen.

Keenan, T. K.; Vallee, R. E.; Powers, J. A.

1972-01-01

384

Process for immobilizing plutonium into vitreous ceramic waste forms  

DOEpatents

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Feng, Xiangdong (Richland, WA); Einziger, Robert E. (Richland, WA)

1997-01-01

385

Process for immobilizing plutonium into vitreous ceramic waste forms  

DOEpatents

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Feng, X.; Einziger, R.E.

1997-01-28

386

Neutronic analysis of a proposed plutonium recycle assembly  

E-print Network

A method for the neutronic analysis of plutonium recycle assemblies has been developed with emphasis on relative power distribution prediction in the boundary area of vastly different spectral regions. Such regions are ...

Solan, George Michael

1975-01-01

387

Solubility of plutonium and uranium in alkaline salt solutions  

SciTech Connect

The solubility of plutonium and uranium in alkaline salt solutions, which will be processed in the In-Tank Precipitation (ITP) process, was investigated to screen for significant factors and interactions among the factors comprising the salt solutions. The factors included in the study were hydroxide, nitrate, nitrite, aluminate, sulfate, carbonate, and temperature. Over the range of factor concentrations studied, the level of hydroxide in the solution is not sufficient alone to predict the resulting concentration of plutonium and uranium in the solution. Other constituents of the salt solution play an important role in determining the amount of plutonium and uranium in solution. Statistical models predicting the plutonium and uranium concentrations over the range of salt solutions investigated are provided.

Hobbs, D.T.; Edwards, T.B.; Fleischman, S.D.

1993-02-12

388

Handling, Storage, and Disposition of Plutonium and Uranium  

NASA Astrophysics Data System (ADS)

The need to address topics of handling, storage, and disposal of plutonium and uranium is driven by concern about hazards posed by the element and by the worldwide quantity of civilian and military materials. The projected inventory of separated civilian plutonium for use in fabricating mixed-oxide (MOX) reactor fuel during initial decades of this century is constant at about 120 metric tons and a comparable amount of excess military plutonium is anticipated from reductions in nuclear weapon stockpiles (IAEA Report, 1998). Although inventories of civilian material are in oxide form, Pu from weapons programs exists primarily as metal. Plutonium is a radiological toxin (Voelz, 2000); its management in a safe and secure manner is essential for protecting workers, the public, and the environment.

Haschke, John M.; Stakebake, Jerry L.

389

Bulging of cans containing plutonium residues. Summary report  

SciTech Connect

In 1994, two cans in the Lawrence Livermore National Laboratory Plutonium Facility were found to be bulging as a result of the generation of gases form the plutonium ash residues contained in the cans. This report describes the chronology of this discovery, the response actions that revealed other pressurized cans, the analysis of the causes, the short-term remedial action, a followup inspection of the short-term storage packages, and a review of proposed long-term remedial options.

Van Konynenburg, R.A.; Wood, D.H.; Condit, R.H.; Shikany, S.D.

1996-03-01

390

Plutonium Immobilization Project System Design Description for Can Loading System  

SciTech Connect

The purpose of this System Design Description (SDD) is to specify the system and component functions and requirements for the Can Loading System and provide a complete description of the system (design features, boundaries, and interfaces), principles of operation (including upsets and recovery), and the system maintenance approach. The Plutonium Immobilization Project (PIP) will immobilize up to 13 metric tons (MT) of U.S. surplus weapons usable plutonium materials.

Kriikku, E.

2001-02-15

391

Recovery of weapon plutonium as feed material for reactor fuel  

SciTech Connect

This report presents preliminary considerations for recovering and converting weapon plutonium from various US weapon forms into feed material for fabrication of reactor fuel elements. An ongoing DOE study addresses the disposition of excess weapon plutonium through its use as fuel for nuclear power reactors and subsequent disposal as spent fuel. The spent fuel would have characteristics similar to those of commercial power spent fuel and could be similarly disposed of in a geologic repository.

Armantrout, G.A.; Bronson, M.A.; Choi, Jor-Shan [and others

1994-03-16

392

PRESSURE DEVELOPMENT IN SEALED CONTAINERS WITH PLUTONIUM BEARING MATERIALS  

Microsoft Academic Search

Gas generation by plutonium-bearing materials in sealed containers has been studied. The gas composition and pressure are determined over periods from months to years. The Pu-bearing materials studied represent those produced by all of the major processes used by DOE in the processing of plutonium and include the maximum amount of water (0.5% by weight) allowed by DOE's 3013 Standard.

J. Duffey; R. Livingston

2010-01-01

393

Weapons-grade plutonium disposition in pressurized water reactors  

Microsoft Academic Search

Studies have been conducted to demonstrate that weapons-grade plutonium can be readily disposed of by utilizing it as a fuel in pressurized water reactors (PWR). The disposition can be achieved by first fabricating the weapons-grade plutonium into a mixed-oxide (MOX) fuel form and then irradiating it in either advanced or existing PWRs to a depleted level similar to commercial spent

D. Biswas; R. W. Rathbun; S. Y. Lee; M. R. Buckner

1995-01-01

394

Application of Physical Methods for Reducing Plutonium Hexafluoride  

Microsoft Academic Search

The exploding-wire method, the photochemical method of irradiation with a light flux from a high-pressure mercury lamp, a high-intensity spark discharge, and irradiation by a CO2 laser are used to reduce plutonium hexafluoride and to separate it from uranium hexafluoride. The dependence of the reduction of plutonium hexafluoride on the wire material, the mass of the reduced product, and the

Yu. V. Drobyshevskii; V. K. Ezhov; E. A. Lobikov; V. N. Prusakov; V. B. Sokolov

2002-01-01

395

Fuel bundle design for enhanced usage of plutonium fuel  

DOEpatents

A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced. 10 figs.

Reese, A.P.; Stachowski, R.E.

1995-08-08

396

Chinese strategic weapons and the plutonium option (U)  

SciTech Connect

In their article "Chinese Strategic Weapons and the Plutonium Option," John W. Lewis and Xue Litai of the Center for International Security and Arms Control at Stanford University's International Strategic Institute present an unclassified look at plutonium processing in the PRC. The article draws heavily on unclassified PRC sources for its short look at this important subject. Interested readers will find more detailed information in the recently available works referenced in the article.

Lewis, John W.; Xui Litai

1988-04-01

397

High absorption efficiency for ingested plutonium in crabs  

Microsoft Academic Search

ALTHOUGH marine organisms have been strongly implicated in the biogeochemical cycle of plutonium, there is disagreement as to whether they can assimilate it efficiently1-7. We have examined the fate of plutonium in a single, worm-crab food chain after ingestion of the isotope which had been metabolically incorporated into the predator's food. Contrary to absorption efficiencies of tenths to hundredths of

Scott W. Fowler; Jean-Claude Guary

1977-01-01

398

Wastes from plutonium conversion and scrap recovery operations  

SciTech Connect

This report deals with the handling of defense-related wastes associated with plutonium processing. It first defines the different waste categories along with the techniques used to assess waste content. It then discusses the various treatment approaches used in recovering plutonium from scrap. Next, it addresses the various waste management approaches necessary to handle all wastes. Finally, there is a discussion of some future areas for processing with emphasis on waste reduction. 91 refs., 25 figs., 4 tabs.

Christensen, D.C.; Bowersox, D.F.; McKerley, B.J.; Nance, R.L.

1988-03-01

399

Assessment of plutonium exposure in the Enewetak population by urinalysis  

SciTech Connect

Since 1980, the inhabitants of Enewetak Atoll have been monitored periodically by scientists from Brookhaven National Laboratory for internally deposited radioactive material. In 1989, the establishment of fission track analysis and of a protocol for shipboard collection of 24-h urine samples significantly improved our ability to assess the internal uptake of plutonium. The purpose of this report is to show the distribution of plutonium concentrations in urine collected in 1989 and 1991, and to assess the associated committed effective doses for the Enewetak population based on a long-term chronic uptake of low-level plutonium. To estimate dose, we derived the plutonium dose-per-unit-uptake coefficients based on the dosimetric system of the International Commission on Radiological Protection. Assuming a continuous uptake, an integrated Jones`s plutonium urine excretion function was developed to interpret the Enewetak urine data. The Appendix shows how these values were derived. The committed effective doses were 0.2 mSv, calculated from the 1991 average plutonium content in 69 urine samples. 29 refs., 3 tabs.

Sun, L.C.; Meinhold, C.B.; Moorthy, A.R. [Brookhaven National Lab., Upton, NY (United States)] [and others

1997-07-01

400

The Concentration of (236)Pu Daughters in Plutonium for Application to MOX Production from Plutonium from Dismantled US Nuclear Weapons  

SciTech Connect

The isotope {sup 236}Pu in the weapons-grade plutonium to be used in the US MOX (mixed-oxide) plant is of concern because the daughter products of {sup 236}Pu are sources of high-energy gamma rays. The {sup 208}Tl daughter of {sup 236}Pu emits intense, high-energy gamma rays that are important for radiation exposure calculations for plant design. It is generally thought that the concentrations of {sup 236}Pu and its daughters are well below 10{sup {minus}10}, but these concentrations are generally below the detection limits of most analytical techniques. One technique that can be used to determine the concentration {sup 208}Tl is the direct measurement of the intensity of the {sup 208}Tl gamma rays in the gamma-ray spectrum from plutonium. Thallium-208 will be in equilibrium with {sup 228}Th, and may very well be in equilibrium with {sup 232}U for most aged plutonium samples. We have used the FRAM isotopic analysis software to analyze dozens of archived high-resolution gamma ray spectra from various samples of US and foreign plutonium. We are able to quantify the ratio of minor isotopes with measurable gamma-ray emissions to the major isotope of plutonium and hence, through the measurement of the plutonium isotopic distribution of the sample, to elemental plutonium itself. Excluding items packaged in fluoropolymer vials, all samples analyzed with {sup 240}Pu < 9% gave {sup 228}Th/Pu ratios < 3.4 e-012 and all samples of US-produced plutonium, including {sup 240}Pu values up to 16.4%, gave {sup 228}Th/Pu ratios < 9.4 e-012. None of these values is significant from a radiation dose standpoint.

Sampson, T.E.; Cremers, T.L.

2001-05-01

401

Plutonium contamination in the environment. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning the ecological impact of plutonium contamination on the environment. Topics examine the effects of plutonium contamination in freshwater and marine sediments, in soil and groundwater, and from nuclear fallout and facilities. Included are applications involving plutonium transport in the food chain, methods of analysis, plutonium bioaccumulation, contamination bioindicators, and plutonium genotoxity. Plutonium distribution changes due to stratification in oxic and anoxic environments are also covered. (Contains a minimum of 52 citations and includes a subject term index and title list.)

Not Available

1994-02-01

402

Plutonium contamination in the environment. (Latest citations from the Selected Water Resources Abstracts database). Published Search  

SciTech Connect

The bibliography contains citations concerning the ecological impact of plutonium contamination on the environment. Topics examine the effects of plutonium contamination in freshwater and marine sediments, in soil and groundwater, and from nuclear fallout and facilities. Included are applications involving plutonium transport in the food chain, methods of analysis, plutonium bioaccumulation, contamination bioindicators, and plutonium genotoxity. Plutonium distribution changes due to stratification in oxic and anoxic environments are also covered. (Contains a minimum of 51 citations and includes a subject term index and title list.)

Not Available

1993-02-01

403

High temperature X-ray diffraction study of the oxidation products and kinetics of uranium-plutonium mixed oxides.  

PubMed

The oxidation products and kinetics of two sets of mixed uranium-plutonium dioxides containing 14%, 24%, 35%, 46%, 54%, and 62% plutonium treated in air were studied by means of in situ X-ray diffraction (XRD) from 300 to 1773 K every 100 K. The first set consisted of samples annealed 2 weeks before performing the experiments. The second one consisted of powdered samples that sustained self-irradiation damage. Results were compared with chosen literature data and kinetic models established for UO2. The obtained diffraction patterns were used to determine the temperature of the hexagonal M3O8 (M for metal) phase formation, which was found to increase with Pu content. The maximum observed amount of the hexagonal phase in wt % was found to decrease with Pu addition. We conclude that plutonium stabilizes the cubic phases during oxidation, but the hexagonal phase was observed even for the compositions with 62 mol % Pu. The results indicate that self-irradiation defects have a slight impact on the kinetics of oxidation and the lattice parameter even after the phase transformation. It was concluded that the lattice constant of the high oxygen phase was unaffected by the changes in the overall O/M when it was in equilibrium with small quantities of M3O8. We propose that the observed changes in the high oxygen cubic phase lattice parameter are a result of either cation migration or an increase in the miscibility of oxygen in this phase. The solubility of Pu in the hexagonal phase was estimated to be below 14 mol % even at elevated temperatures. PMID:25412433

Strach, Michal; Belin, Renaud C; Richaud, Jean-Christophe; Rogez, Jacques

2014-12-15

404

Magnesite disposal of carbon dioxide  

SciTech Connect

In this paper we report our progress on developing a method for carbon dioxide disposal whose purpose it is to maintain coal energy competitive even is environmental and political pressures will require a drastic reduction in carbon dioxide emissions. In contrast to most other methods, our approach is not aiming at a partial solution of the problem, or at buying time for phasing out fossil energy. Instead, its purpose is to obtain a complete and economic solution of the problem, and thus maintain access to the vast fossil energy reservoir. A successful development of this technology would guarantee energy availability for many centuries even if world economic growth the most optimistic estimates that have been put forward. Our approach differs from all others in that we are developing an industrial process which chemically binds the carbon dioxide in an exothermic reaction into a mineral carbonate that is thermodynamically stable and environmentally benign.

Lackner, K.S.; Butt, D.P.; Wendt, C.H.

1997-08-01

405

Molecular Structure of Carbon Dioxide  

NSDL National Science Digital Library

Carbon dioxide was first described in the 17th century by Jan Baptist van Helmont, a Belgium chemist. The chemical CO2 is released into the atmosphere when carbon-containing fossil fuels like oil, natural gas, and coal are burned in air. It is also produced by various microorganisms in fermentation and is breathed out by animals. Plants absorb carbon dioxide during photosynthesis, using both the carbon and the oxygen to construct carbohydrates. Every year the amount of CO2 in the atmosphere is increasing. CO2 build-up in the atmosphere is caused by deforestation, therefore reducing the number of trees available to absorb CO2. Excess CO2 in the environment causes Global Warming and the Greenhouse Effect. It is also toxic to humans since inhalation of large amounts of CO2 can cause suffocation. Some beverages, such as beer and sparkling wine contain carbon dioxide as a result of fermentation.

2002-08-15

406

Benchmark Evaluation of Plutonium Nitrate Solution Arrays  

SciTech Connect

In October and November of 1981 thirteen approach-to-critical experiments were performed on a remote split table machine (RSTM) in the Critical Mass Laboratory of Pacific Northwest Laboratory (PNL) in Richland, Washington, using planar arrays of polyethylene bottles filled with plutonium (Pu) nitrate solution. Arrays of up to sixteen bottles were used to measure the critical number of bottles and critical array spacing with a tight fitting Plexiglas{reg_sign} reflector on all sides of the arrays except the top. Some experiments used Plexiglas shells fitted around each bottles to determine the effect of moderation on criticality. Each bottle contained approximately 2.4 L of Pu(NO3)4 solution with a Pu content of 105 g Pu/L and a free acid molarity H+ of 5.1. The plutonium was of low 240Pu (2.9 wt.%) content. These experiments were performed to fill a gap in experimental data regarding criticality limits for storing and handling arrays of Pu solution in reprocessing facilities. Of the thirteen approach-to-critical experiments eleven resulted in extrapolations to critical configurations. Four of the approaches were extrapolated to the critical number of bottles; these were not evaluated further due to the large uncertainty associated with the modeling of a fraction of a bottle. The remaining seven approaches were extrapolated to critical array spacing of 3-4 and 4-4 arrays; these seven critical configurations were evaluation for inclusion as acceptable benchmark experiments in the International Criticality Safety Benchmark Evaluation Project (ICSBEP) Handbook. Detailed and simple models of these configurations were created and the associated bias of these simplifications was determined to range from 0.00116 and 0.00162 {+-} 0.00006 ?keff. Monte Carlo analysis of all models was completed using MCNP5 with ENDF/BVII.0 neutron cross section libraries. A thorough uncertainty analysis of all critical, geometric, and material parameters was performed using parameter perturbation methods. It was found that uncertainty in the impurities in the polyethylene bottles, reflector position, bottle outer diameter, and critical array spacing had the largest effect. The total uncertainty ranged from 0.00651 to 0.00920 ?keff. Evaluation methods and results will be presented and discussed in greater detail in the full paper.

M. A. Marshall; J. D. Bess

2011-09-01

407

Carbon Dioxide - Our Common "Enemy"  

NASA Technical Reports Server (NTRS)

Health effects of brief and prolonged exposure to carbon dioxide continue to be a concern for those of us who manage this pollutant in closed volumes, such as in spacecraft and submarines. In both examples, considerable resources are required to scrub the atmosphere to levels that are considered totally safe for maintenance of crew health and performance. Defining safe levels is not a simple task because of many confounding factors, including: lack of a robust database on human exposures, suspected significant variations in individual susceptibility, variations in the endpoints used to assess potentially adverse effects, the added effects of stress, and the fluid shifts associated with micro-gravity (astronauts only). In 2007 the National Research Council proposed revised Continuous Exposure Guidelines (CEGLs) and Emergency Exposure Guidelines (EEGLs) to the U.S. Navy. Similarly, in 2008 the NASA Toxicology Group, in cooperation with another subcommittee of the National Research Council, revised Spacecraft Maximum Allowable Concentrations (SMACs). In addition, a 1000-day exposure limit was set for long-duration spaceflights to celestial bodies. Herein we examine the rationale for the levels proposed to the U.S. Navy and compare this rationale with the one used by NASA to set its limits. We include a critical review of previous studies on the effects of exposure to carbon dioxide and attempt to dissect out the challenges associated with setting fully-defensible limits. We also describe recent experiences with management of carbon dioxide aboard the International Space Station with 13 persons aboard. This includes the tandem operations of the Russian Vozduk and the U.S. Carbon Dioxide Removal System. A third removal system is present while the station is docked to the Shuttle spacecraft, so our experience includes the lithium hydroxide system aboard Shuttle for the removal of carbon dioxide. We discuss strategies for highly-efficient, regenerable removal of carbon dioxide that could meet the 1000-day SMAC of 0.5%, which would apply to long-duration voyages to Mars.

James, John T.; Macatangay, Ariel

2009-01-01

408

21 CFR 73.2575 - Titanium dioxide.  

Code of Federal Regulations, 2014 CFR

...specifications. The color additive titanium dioxide shall...restrictions. The color additive titanium dioxide may...consistent with good manufacturing practice. (c) Labeling...requirements. The color additive and any mixtures...

2014-04-01

409

21 CFR 73.2575 - Titanium dioxide.  

Code of Federal Regulations, 2011 CFR

...specifications. The color additive titanium dioxide shall...restrictions. The color additive titanium dioxide may...consistent with good manufacturing practice. (c) Labeling...requirements. The color additive and any mixtures...

2011-04-01

410

21 CFR 73.2575 - Titanium dioxide.  

Code of Federal Regulations, 2013 CFR

...LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2575 Titanium dioxide. (a) Identity...additive titanium dioxide may be safely used in cosmetics, including cosmetics intended for use in the area of the eye, in...

2013-04-01

411

21 CFR 73.2575 - Titanium dioxide.  

Code of Federal Regulations, 2012 CFR

...LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2575 Titanium dioxide. (a) Identity...additive titanium dioxide may be safely used in cosmetics, including cosmetics intended for use in the area of the eye, in...

2012-04-01

412

Seventh International Carbon Dioxide Conference  

NSDL National Science Digital Library

Organized by NOAA's Climate Monitoring and Diagnostic Laboratory (CMDL), the Seventh International Carbon Dioxide Conference is planned September 25-30 in Broomfield, Colo. At this website, scientists involved in various aspects of the global carbon cycle, especially the current increases of carbon dioxide in the atmosphere, are encouraged to attend. Users can read the preliminary announcement and can learn about the themes of the conference. Researchers can learn about abstract submissions and accommodations. The Brief Conference History link offers a nice synopsis of the accomplishments of past conferences.

413

Fast Thorium Molten Salt Reactors Started with Plutonium  

SciTech Connect

One of the pending questions concerning Molten Salt Reactors based on the {sup 232}Th/{sup 233}U fuel cycle is the supply of the fissile matter, and as a consequence the deployment possibilities of a fleet of Molten Salt Reactors, since {sup 233}U does not exist on earth and is not yet produced in the current operating reactors. A solution may consist in producing {sup 233}U in special devices containing Thorium, in Pressurized Water or Fast Neutrons Reactors. Two alternatives to produce {sup 233}U are examined here: directly in standard Molten Salt Reactors started with Plutonium as fissile matter and then operated in the Th/{sup 233}U cycle; or in dedicated Molten Salt Reactors started and fed with Plutonium as fissile matter and Thorium as fertile matter. The idea is to design a critical reactor able to burn the Plutonium and the minor actinides presently produced in PWRs, and consequently to convert this Plutonium into {sup 233}U. A particular reactor configuration is used, called 'unique channel' configuration in which there is no moderator in the core, leading to a quasi fast neutron spectrum, allowing Plutonium to be used as fissile matter. The conversion capacities of such Molten Salt Reactors are excellent. For Molten Salt Reactors only started with Plutonium, the assets of the Thorium fuel cycle turn out to be quickly recovered and the reactor's characteristics turn out to be equivalent to Molten Salt Reactors operated with {sup 233}U only. Using a combination of Molten Salt Reactors started or operated with Plutonium and of Molten Salt Reactors started with {sup 233}U, the deployment capabilities of these reactors fully satisfy the condition of sustainability. (authors)

Merle-Lucotte, E.; Heuer, D.; Le Brun, C.; Brissot, R.; Liatard, E.; Meplan, O.; Nuttin, A. [LPSC/IN2P3/CNRS, 53, avenue des Martyrs, F-38026 Grenoble Cedex (France); Mathieu, L. [CENBG, Le Haut-Vigneau, BP 120, F-33175 Gradignan Cedex (France)

2006-07-01

414

Nitrogen dioxide, sulfur dioxide, and ammonia detector for remote sensing of vehicle emissions  

E-print Network

Nitrogen dioxide, sulfur dioxide, and ammonia detector for remote sensing of vehicle emissions the capability to measure nitrogen dioxide in the UV with one spectrometer and to measure SO2 and NH3 along with sulfuric and nitric acids formed from at- mospheric oxidations of sulfur dioxide SO2 and nitrogen oxides

Denver, University of

415

VAPOR + LIQUID EQUILIBRIUM OF WATER, CARBON DIOXIDE, AND THE BINARY SYSTEM WATER + CARBON DIOXIDE FROM  

E-print Network

VAPOR + LIQUID EQUILIBRIUM OF WATER, CARBON DIOXIDE, AND THE BINARY SYSTEM WATER + CARBON DIOXIDE the vapor-liquid equilibrium of water (between 323 and 573 K), carbon dioxide (between 230 and 290 K) and their binary mixtures (between 348 and 393 K). The properties of supercritical carbon dioxide were determined

416

Application of Prompt Gamma-Ray Analysis to Identify Electrorefining Salt-Bearing Plutonium Oxide at the Plutonium Finishing Plant  

SciTech Connect

Prompt gamma-ray analysis is being implemented at the Plutonium Finishing Plant (PFP) to screen impure plutonium oxide inventory items, received in the mid-1980s from the Rocky Flats Plant, for the presence of sodium chloride and potassium chloride salts from the electrorefining process. A large fraction of these items are suspected to contain electrorefining salts. Because the salts evaporate at the=950C stabilization temperature mandated for long-term storage under the U.S. Department of Energy plutonium oxide stabilization and storage criteria to plug and corrode process equipment, items found to have these salts qualify for thermal stabilization at 750C. The prompt gamma ray energies characteristic of sodium, potassium, chlorine, and other low atomic weight elements arise from the interaction the light elements with alpha radiation from plutonium and americium radioactive decay. High-resolution gamma ray spectrometers designed to detect energies up to {approx}4.5 MeV are used to gather the high-energy prompt gamma spectra.Observation of the presence of the high-energy gamma peaks representing the natural chlorine-35, sodium-23, and potassium-39 isotopes and the sodium-to-chlorine peak area ratios in the range for plutonium oxide materials known to contain the electrorefining salts give the evidence needed to identify plutonium oxide materials at the PFP that qualify for the lower-temperature processing. Conversely, the absence of these telltale signals in the prompt gamma analysis provides evidence that the materials do not contain the electrorefining salts. Furthermore, based on calibrations using known assayed items, semiquantitative measurement of the quantity of chlorine present in materials containing electrorefining salt also can be performed by using the count rates observed for the chlorine peak, the plutonium quantity present in the measured item, and the plutonium- and chlorine-specific response of the gamma detection system. The origin and characteristics of the impure plutonium oxide, the process impacts of the electrorefining salts, and the background and technical bases of application of prompt gamma-ray analysis to identify electrorefining salt-bearing plutonium oxide at the PFP are described.

Fazzari, Dennis M. (FLUOR HANFORD, INC); Jones, Susan A. (FLUOR HANFORD, INC); Delegard, Calvin H. (BATTELLE (PACIFIC NW LAB))

2003-09-25

417

Carbon dioxide transport over complex terrain  

USGS Publications Warehouse

The nocturnal transport of carbon dioxide over complex terrain was investigated. The high carbon dioxide under very stable conditions flows to local low-ground. The regional drainage flow dominates the carbon dioxide transport at the 6 m above the ground and carbon dioxide was transported to the regional low ground. The results show that the local drainage flow was sensitive to turbulent mixing associated with local wind shear.

Sun, J.; Burns, S.P.; Delany, A.C.; Oncley, S.P.; Turnipseed, A.; Stephens, B.; Guenther, A.; Anderson, D.E.; Monson, R.

2004-01-01

418

Plutonium solution analyzer. Revised February 1995  

SciTech Connect

A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%--0.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40--240 g/l: and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4--4.0 g/y. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 ml of each sample and standard, and generates waste at the rate of about 1.5 ml per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded).

Burns, D.A.

1995-02-01

419

21 CFR 73.2575 - Titanium dioxide.  

Code of Federal Regulations, 2010 CFR

21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.2575... The color additive titanium dioxide shall conform...on § 73.575 (a)(1) and (b). (b... The color additive titanium dioxide may be...

2010-04-01

420

21 CFR 73.3126 - Titanium dioxide.  

Code of Federal Regulations, 2010 CFR

21 Food and Drugs 1 2010-04-01 2010-04-01 false Titanium dioxide. 73.3126...Devices § 73.3126 Titanium dioxide. (a) Identity... The color additive titanium dioxide (CAS Reg...of § 73.575(a)(1) and (b)....

2010-04-01

421

Introduction Air Quality and Nitrogen Dioxide  

E-print Network

Introduction Air Quality and Nitrogen Dioxide Air pollution can be defined as "the presence worldwide" WHO Air quality guidelines for particulate matter, ozone, nitrogen dioxide and sulphur dioxide directives have implemented Air Quality Management Areas (AQMAs); these are areas where air quality standards

422

7Carbon Dioxide Increases The Keeling Curve,  

E-print Network

7Carbon Dioxide Increases The Keeling Curve, shown to the left, shows the variation in concentration of atmospheric carbon dioxide since 1958-1974. It is based on continuous measurements taken of rapidly increasing carbon dioxide levels in the atmosphere. Additional measurements by scientists working

423

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW  

E-print Network

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW J. E. Santos1 1 Department of Mathematics, Purdue University, USA Purdue University, March 1rst, 2013 SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12 (North Sea). SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12;Introduction. II CO2 is separated

Santos, Juan

424

21 CFR 184.1240 - Carbon dioxide.  

Code of Federal Regulations, 2014 CFR

...3 2014-04-01 2014-04-01 false Carbon dioxide. 184.1240 Section 184.1240 Food and...Specific Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2 , CAS Reg....

2014-04-01

425

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW  

E-print Network

SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW J. E. Santos1, G. B. Savioli2, J. M. Carcione3, D´e, Argentina SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12;Introduction. I Storage of CO2). SEISMIC MONITORING OF CARBON DIOXIDE FLUID FLOW ­ p. #12;Introduction. II CO2 is separated from natural

Santos, Juan

426

Carbon dioxide storage professor Martin Blunt  

E-print Network

Carbon dioxide storage professor Martin Blunt executive summary Carbon Capture and Storage (CCS) referS to the Set of technologies developed to capture carbon dioxide (Co2) gas from the exhausts of technologies developed to capture carbon dioxide (Co2) gas from the exhausts of power stations and from other

427

2, 18491865, 2005 Carbon dioxide in  

E-print Network

BGD 2, 1849­1865, 2005 Carbon dioxide in southern Poland L. Chmura et al. Title Page Abstract is licensed under a Creative Commons License. 1849 #12;BGD 2, 1849­1865, 2005 Carbon dioxide in southern urban environment with numerous local sources of carbon dioxide. Despite of relative proximity of those

Paris-Sud XI, Université de

428

Method and apparatus for producing chlorine dioxide  

Microsoft Academic Search

A continuous method and apparatus are described for the efficient production of gaseous chlorine dioxide by the reaction between gaseous sulfur dioxide and an aqueous solution of a metallic chlorate. The chlorate solution and a highly concentrated sulfur dioxide gas are introduced into a packed columnar chamber at closely adjacent locations at the bottom of the chamber so as to

P. W. Santillie; D. M. Ramras

1984-01-01

429

Fluoropolymer-based capacitive carbon dioxide sensor  

Microsoft Academic Search

We describe a thin film sensor of carbon dioxide which relies on the change in capacitance of a fluoropolymer thin film caused by the difference in dielectric constants between air and carbon dioxide and by the preferred adsorption by the polymer of carbon dioxide compared to that of air. The fluoropolymer, Teflon AF 2400™, selectively adsorbs large quantities of CO2

Paul L. Kebabian; Andrew Freedman

2006-01-01

430

Rate Constant Ratios During Nitrogen Dioxide Photolysis  

Microsoft Academic Search

Nitrogen dioxide is the light absorber in the hydrocarbon system leading to production of photochemical air pollution. Studies of the reactions involved are based on the kinetics of nitrogen dioxide photolysis and the values of the rate constants derived therefrom. The photolysis of nitrogen dioxide was investigated in the 2-20 ppm concentration range. The value of the bimolecular rate constant

E. A. Schuck; E. R. Stephens; R. R. Schrock

1966-01-01

431

PLUTONIUM LOADING CAPACITY OF REILLEX HPQ ANION EXCHANGE COLUMN - AFS-2 PLUTONIUM FLOWSHEET FOR MOX  

SciTech Connect

Radioactive plutonium (Pu) anion exchange column experiments using scaled HB-Line designs were performed to investigate the dependence of column loading performance on the feed composition in the H-Canyon dissolution process for plutonium oxide (PuO{sub 2}) product shipped to the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). These loading experiments show that a representative feed solution containing {approx}5 g Pu/L can be loaded onto Reillex{trademark} HPQ resin from solutions containing 8 M total nitrate and 0.1 M KF provided that the F is complexed with Al to an [Al]/[F] molar ratio range of 1.5-2.0. Lower concentrations of total nitrate and [Al]/[F] molar ratios may still have acceptable performance but were not tested in this study. Loading and washing Pu losses should be relatively low (<1%) for resin loading of up to 60 g Pu/L. Loading above 60 g Pu/L resin is possible, but Pu wash losses will increase such that 10-20% of the additional Pu fed may not be retained by the resin as the resin loading approaches 80 g Pu/L resin.

Kyser, E.; King, W.; O'Rourke, P.

2012-07-26

432

Prospective studies of HTR fuel cycles involving plutonium  

SciTech Connect

High Temperature Gas Cooled reactors (HTRs) are able to accommodate a wide variety of mixtures of fissile and fertile materials without any significant modification of the core design. This flexibility is due to an uncoupling between the parameters of cooling geometry, and the parameters which characterize neutronic optimisation (moderation ratio or heavy nuclide concentration and distribution). Among other advantageous features, an HTR core has a better neutron economy than a LWR because there is much less parasitic capture in the moderator (capture cross section of graphite is 100 times less than the one of water) and in internal structures. Moreover, thanks to the high resistance of the coated particles, HTR fuels are able to reach very high burn-ups, far beyond the possibilities offered by other fuels (except the special case of molten salt reactors). These features make HTRs especially interesting for closing the nuclear fuel cycle and stabilizing the plutonium inventory. A large number of fuel cycle studies are already available today, on 3 main categories of fuel cycles involving HTRs: i) High enriched uranium cycle, based on thorium utilization as a fertile material and HEU as a fissile material; ii) Low enriched uranium cycle, where only LEU is used (from 5% to 12%); iii) Plutonium cycle based on the utilization of plutonium only as a fissile material, with (or without) fertile materials. Plutonium consumption at high burnups in HTRs has already been tested with encouraging results under the DRAGON project and at Peach Bottom. To maximize plutonium consumption, recent core studies have also been performed on plutonium HTR cores, with special emphasis on weapon-grade plutonium consumption. In the following, we complete the picture by a core study for a HTR burning reactor-grade plutonium. Limits in burnup due to core neutronics are investigated for this type of fuel. With these limits in mind, we study in some detail the Pu cycle in the special case of a reactor fleet made of a mixture of LWRs and HTRs. It is reasonable to assume that if HTRs are to be deployed on an industrial scale, they will co-exist during a long period of time with already existing LWRs. The present paper investigates the symbiotic behaviour of LWRs producing plutonium, and of HTRs burning it. (authors)

Bonin, B.; Greneche, D. [COGEMA, Direction de la Recherche et du Developpement (France); Carre, F.; Damian, F.; Doriath, J.Y. [CEA Direction de l'Energie Nucleaire (France)

2002-07-01

433

Reduction of Worldwide Plutonium Inventories Using Conventional Reactors and Advanced Fuels: A Systems Study  

SciTech Connect

The potential for reducing plutonium inventories in the civilian nuclear fuel cycle through recycle in LWRs of a variety of mixed oxide forms is examined by means of a cost based plutonium flow systems model. This model emphasizes: (1) the minimization of separated plutonium; (2) the long term reduction of spent fuel plutonium; (3) the optimum utilization of uranium resources; and (4) the reduction of (relative) proliferation risks. This parametric systems study utilizes a globally aggregated, long term (approx. 100 years) nuclear energy model that interprets scenario consequences in terms of material inventories, energy costs, and relative proliferation risks associated with the civilian fuel cycle. The impact of introducing nonfertile fuels (NFF,e.g., plutonium oxide in an oxide matrix that contains no uranium) into conventional (LWR) reactors to reduce net plutonium generation, to increase plutonium burnup, and to reduce exo- reactor plutonium inventories also is examined.

Krakowski, R.A., Bathke, C.G.

1997-12-31

434

Amarillo National Resource Center for Plutonium. Quarterly technical progress report, May 1, 1997--July 31, 1997  

SciTech Connect

Progress summaries are provided from the Amarillo National Center for Plutonium. Programs include the plutonium information resource center, environment, public health, and safety, education and training, nuclear and other material studies.

NONE

1997-09-01

435

Amarillo National Resource Center for Plutonium. Quarterly technical progress report, February 1, 1998--April 30, 1998  

SciTech Connect

Activities from the Amarillo National Resource Center for Plutonium are described. Areas of work include materials science of nuclear and explosive materials, plutonium processing and handling, robotics, and storage.

NONE

1998-06-01

436

1. West facade of Plutonium Concentration Facility (Building 233S), ReductionOxidation ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. West facade of Plutonium Concentration Facility (Building 233-S), Reduction-Oxidation Building (REDOX-202-S) to the right. Looking east. - Reduction-Oxidation Complex, Plutonium Concentration Facility, 200 West Area, Richland, Benton County, WA

437

1. VIEW LOOKING NORTHWEST AT BUILDING 776/777, THE PLUTONIUM PROCESSING ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. VIEW LOOKING NORTHWEST AT BUILDING 776/777, THE PLUTONIUM PROCESSING BUILDING, DURING CONSTRUCTION. (4/10/56) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

438

Development of an Automatic Method for Americium and Plutonium Separation and  

E-print Network

Development of an Automatic Method for Americium and Plutonium Separation and Preconcentration hydrochloric acid, and then plutonium is separated via on-column Pu- (IV) reduction to Pu(III) with titanium

Sánchez, David

439

PLUTONIUM/HIGH-LEVEL VITRIFIED WASTE BDBE DOSE CALCULATION  

SciTech Connect

The purpose of this calculation is to provide a dose consequence analysis of high-level waste (HLW) consisting of plutonium immobilized in vitrified HLW to be handled at the proposed Monitored Geologic Repository at Yucca Mountain for a beyond design basis event (BDBE) under expected conditions using best estimate values for each calculation parameter. In addition to the dose calculation, a plutonium respirable particle size for dose calculation use is derived. The current concept for this waste form is plutonium disks enclosed in cans immobilized in canisters of vitrified HLW (i.e., glass). The plutonium inventory at risk used for this calculation is selected from Plutonium Immobilization Project Input for Yucca Mountain Total Systems Performance Assessment (Shaw 1999). The BDBE examined in this calculation is a nonmechanistic initiating event and the sequence of events that follow to cause a radiological release. This analysis will provide the radiological releases and dose consequences for a postulated BDBE. Results may be considered in other analyses to determine or modify the safety classification and quality assurance level of repository structures, systems, and components. This calculation uses best available technical information because the BDBE frequency is very low (i.e., less than 1.0E-6 events/year) and is not required for License Application for the Monitored Geologic Repository. The results of this calculation will not be used as part of a licensing or design basis.

J.A. Ziegler

2000-11-20

440

Plutonium movements across the haemochorial placenta of the guinea pig.  

PubMed

In order to measure transplacental movements of plutonium without the complications of fetal accumulation, the fetal circulation of the guinea pig placenta (at 59 to 61 days of gestation) was perfused in situ. Dams were administered trace quantities of tritiated water (to indicate changes in maternal blood flow to the placenta) and 30 mu Ci/kg (i.e., approximately 500 micrograms/kg) of citrated 239Pu by intravenous injection. Plutonium-239 doses were large, approaching the LD50/30 (20 to 80 mu Ci/kg) for other species. Perfusion pressure, maternal cardiac rate, electrocardiogram, blood pressure, and respiratory rate were monitored continuously during each perfusion. Our measurements show that the clearance of plutonium from mother to fetus is small--2.5 +/- 0.5 microliter/min--an amount that is less than 20 per cent of the clearance of inorganic mercury. The indirect measurements of maternal blood flow to the placenta indicate that placental blood flow is greatly diminished in dams dosed with plutonium, which may partially account for the low clearance of plutonium. PMID:6963964

Kelman, B J; Sikov, M R

1981-01-01

441

Plutonium disposition study phase 1b final report  

SciTech Connect

This report provides the results of the Westinghouse activities performed as part of the Plutonium Disposition Study Phase 1b. These activities, which took place from May 16, 1993 to September 15, 1993, build upon the work completed in Phase 1a, which concluded on May 15, 1993. In Phase 1a, three Plutonium Disposal Reactor (PDR) options were developed for the disposal of excess weapons grade plutonium from returned and dismantled nuclear weapons. This report documents the results of several tasks that were performed to further knowledge in specific areas leading up to Phase 2 of the PDR Study. The Westinghouse activities for Phase 1b are summarized as follows: (1) resolved technical issues concerning reactor physics including equilibrium cycle calculations, use of gadolinium, moderator temperature coefficient, and others as documented in Section 2.0; (2) analyzed large Westinghouse commercial plants for plutonium disposal; (3) reactor safety issues including the steam line break were resolved, and are included in Section 2.0; (4) several tasks related to the PDR Fuel Cycle were examined; (5) cost and deployment options were examined to determine optimal configuration for both plutonium disposal and tritium production; (6) response to questions from DOE and National Academy of Scientists (NAS) reviewers concerning the PDR Phase 1a report are included in Appendix A.

NONE

1993-09-15

442

Neutron monitoring of plutonium at the ZPPR storage vault  

SciTech Connect

We investigated a method for monitoring a typical large storage vault for unauthorized removal of plutonium. The method is based on the assumption that the neutron field in a vault produced by a particular geometric configuration of bulk plutonium remains constant in time and space as long as the configuration is undisturbed. To observe such a neutron field, we installed an array of 25 neutron detectors in the ceiling of a plutonium storage vault at Argonne National Laboratory West. Each neutron detector provided an independent spatial measurement of the vault neutron field. Data collected by each detector were processed to determine whether statistically significant changes had occurred in the neutron field. Continuous observation experiments measured the long-term stability of the system. Removal experiments were performed in which known quantities of plutonium were removed from the vault. Both types of experiments demonstrated that the neutron monitoring system can detect removal or addition of bulk plutonium (11% /sup 240/Pu) whose mass is as small as 0.04% of the total inventory.

Caldwell, J.T.; Kuckertz, T.H.; Bieri, J.M.; France, S.W.; Goin, R.W.; Hastings, R.D.; Pratt, J.C.; Shunk, E.R.

1981-12-01

443

Antineutrino monitoring of burning mixed oxide plutonium fuels  

NASA Astrophysics Data System (ADS)

Background: Antineutrino monitoring of reactors is an enhanced nuclear safeguard that is being explored by several international groups. A key question is whether such a scheme could be used to verify the destruction of plutonium loaded in a reactor as mixed oxide (MOX) fuel.Purpose: To explore the effectiveness of antineutrino monitoring for the purposes of nuclear accountability and safeguarding of MOX plutonium, we examine the magnitude and temporal variation in the antineutrino signals expected for different loadings of MOX fuels.Methods: Reactor burn simulations are carried out for four different MOX fuel loadings and the antineutrino signals as a function of fuel burnup are computed and compared.Results: The antineutrino signals from reactor-grade and weapons-grade MOX are shown to be distinct from those from burning low enriched uranium, and this signal difference increases as the MOX plutonium fraction of the reactor core increases.Conclusion: Antineutrino monitoring could be used to verify the destruction of plutonium in reactors, although verifying the grade of the plutonium being burned is found to be more challenging.

Hayes, A. C.; Trellue, H. R.; Nieto, Michael Martin; Wilson, W. B.

2012-02-01

444

VOLTAMMETRIC MEMBRANE CHLORINE DIOXIDE ELECTRODE  

EPA Science Inventory

A voltammetric membrane electrode system has been modified and applied to the in situ measurement of chlorine dioxide. The electrode system consisted of a gold cathode, a silver/silver chloride reference electrode, and a gold counter electrode. Different membrane materials were t...

445

SULFUR DIOXIDE SOURCES IN AK  

EPA Science Inventory

This map shows industrial plants which emit 100 tons/year or more of sulfur dioxide (SO2) in Alaska. The SO2 sources are plotted on a background map of cities and county boundaries. Data Sources: SO2 Sites: U.S. EPA AIRS System, County Outlines: 1990 Census Tiger Line Files 1:1...

446

Modelling Sublimation of Carbon Dioxide  

ERIC Educational Resources Information Center

In this article, the author reports results in their efforts to model sublimation of carbon dioxide and the associated kinetics order and parameter estimation issues in their model. They have offered the reader two sets of data and several approaches to determine the rate of sublimation of a piece of solid dry ice. They presented several models…

Winkel, Brian

2012-01-01

447

Sulfur Dioxide and Material Damage  

ERIC Educational Resources Information Center

This study relates sulfur dioxide levels with material damage in heavily populated or polluted areas. Estimates of loss were determined from increased maintenance and replacement costs. The data indicate a decrease in losses during the past five years probably due to decline in pollution levels established by air quality standards. (MR)

Gillette, Donald G.

1975-01-01

448

Colloid Transport of Plutonium in the Far-Field of the Mayak Production Association, Russia  

Microsoft Academic Search

Sorption of actinides, particularly plutonium, onto submicrometer-sized colloids increases their mobility, but these plutonium colloids are difficult to detect in the far-field. We identified actinides on colloids in the groundwater from the Mayak Production Association, Urals, Russia; at the source, the plutonium activity is ~1000 becquerels per liter. Plutonium activities are still 0.16 becquerels per liter at a distance of

Alexander P. Novikov; Stepan N. Kalmykov; Satoshi Utsunomiya; Rodney C. Ewing; François Horreard; Alex Merkulov; Sue B. Clark; Vladimir V. Tkachev; Boris F. Myasoedov

2006-01-01

449

SUPPORTING SAFE STORAGE OF PLUTONIUM-BEARING MATERIALS THROUGH SCIENCE, ENGINEERING AND SURVEILLANCE  

Microsoft Academic Search

Reductions in the size of the U. S. nuclear weapons arsenal resulted in the need to store large quantities of plutonium-bearing metals and oxides for prolonged periods of time. To assure that the excess plutonium from the U. S. Department of Energy (DOE) sites was stored in a safe and environmentally friendly manner the plutonium-bearing materials are stabilized and packaged

K. Dunn; G. Chandler; C. Gardner; M. Louthan; J. Mcclard

2009-01-01

450

Implications of plutonium utilization strategies on the transition from a LWR economy to a breeder economy  

Microsoft Academic Search

The plutonium interface between the LWR and LMFBR fuel cycles is examined for typical nuclear growth projections both with and without plutonium recycle in LWRs. In order to guarantee a fuel supply for projected LMFBR growth rates, significant multiple Pu recycle in LWRs will not be possible. However, about 78% of the benefit of multiple plutonium recycle between now and

D. F. Newman; R. M. Fleischman; M. K. White

1977-01-01

451

Dry sample storage system for an analytical laboratory supporting plutonium processing  

Microsoft Academic Search

The Special Isotope Separation (SIS) plant is designed to provide removal of undesirable isotopes in fuel grade plutonium by the atomic vapor laser isotope separation (AVLIS) process. The AVLIS process involves evaporation of plutonium metal, and passage of an intense beam of light from a laser through the plutonium vapor. The laser beam consists of several discrete wavelengths, tuned to

H. A. Treibs; S. D. Hartenstein; B. L. Griebenow; M. A. Wade

1990-01-01

452

A probabilistic risk assessment of the LLNL Plutonium facility`s evaluation basis fire operational accident  

Microsoft Academic Search

The Lawrence Livermore National Laboratory (LLNL) Plutonium Facility conducts numerous involving plutonium to include device fabrication, development of fabrication techniques, metallurgy research, and laser isotope separation. A Safety Analysis Report (SAR) for the building 332 Plutonium Facility was completed rational safety and acceptable risk to employees, the public, government property, and the environment. This paper outlines the PRA analysis of

Brumburgh

1994-01-01

453

Safety considerations for an accelerator-driven molten-salt plutonium burner  

Microsoft Academic Search

Accelerator-driven transmutation technologies have been under study at Los Alamos National Laboratory (LANL) for several years for application to nuclear waste treatment, tritium production, and energy generation. Recently, application of this technology to the disposition of excess weapons plutonium has been considered. The goals for this application are to achieve efficient plutonium burning without producing additional plutonium, to provide the

C. R. Bell; M. G. Houts

1994-01-01

454

Mastering the art of plutonium pit production to ensure national security  

E-print Network

- 1 - Mastering the art of plutonium pit production to ensure national security April 24, 2012 #12;- 2 - #12;- 3 - Plutonium pit manufacturing meets goals, prepares for future needs: reviving a lost art necessary for national security On August 17, 2011 Los Alamos National Laboratory's Plutonium

455

j . Phycol. 17, 346-352 (1981) SORPTION OF PLUTONIUM-237 BY TWO SPECIES OF  

E-print Network

j . Phycol. 17, 346-352 (1981) SORPTION OF PLUTONIUM-237 BY TWO SPECIES OF MARINE PHYTOPLANKTON factor; phytoplankton, ma- rine; radionuclide; plutonium-237; sorption kinetics, pas- sive mechanism in the biological control of radionuclide distribtuion in aquatic systems. Algae, when exposed to plutonium

Yen, Jeannette

456

Plutonium-238 observations as a test of modeled transport and surface deposition of meteoric smoke particles  

E-print Network

Plutonium-238 observations as a test of modeled transport and surface deposition of meteoric smoke chemistry-climate model (CCM) to simulate the transport and deposition of plutonium- 238 oxide nanoparticles. P. Chipperfield, and J. M. C. Plane (2013), Plutonium-238 observations as a test of modeled

Chipperfield, Martyn

457

Spectral Properties of -Plutonium: Sensitivity to 5f Occupancy Jian-Xin Zhu,1  

E-print Network

Spectral Properties of -Plutonium: Sensitivity to 5f Occupancy Jian-Xin Zhu,1 A. K. McMahan,2 M. D a systematic analysis of the spectral properties of -plutonium with varying 5f occupancy. The LDA Hamiltonian properties, crystal structure, and metallurgy, plutonium is probably the most complicated element

458

Ris-R-1321(EN) On Weapons Plutonium in the Arctic  

E-print Network

Risø-R-1321(EN) On Weapons Plutonium in the Arctic Environment (Thule, Greenland) Mats Eriksson Risø National Laboratory, Roskilde, Denmark April 2002 #12;Risø­R­1321(EN) On Weapons Plutonium; that plutonium is not transported from the contaminated sediments into the surface water in this shelf sea

459

Relativistic density functional theory modeling of plutonium and americium higher oxide molecules  

E-print Network

Relativistic density functional theory modeling of plutonium and americium higher oxide molecules of plutonium and americium higher oxide molecules Andréi Zaitsevskii,1,2,a) Nikolai S. Mosyagin,2,3 Anatoly V of plutonium and americium higher oxide molecules (actinide oxidation states VI through VIII) by two

Titov, Anatoly

460

Standard practice for preparation and dissolution of plutonium materials for analysis  

E-print Network

1.1 This practice is a compilation of dissolution techniques for plutonium materials that are applicable to the test methods used for characterizing these materials. Dissolution treatments for the major plutonium materials assayed for plutonium or analyzed for other components are listed. Aliquants of the dissolved samples are dispensed on a weight basis when one of the analyses must be highly reliable, such as plutonium assay; otherwise they are dispensed on a volume basis. 1.2 The treatments, in order of presentation, are as follows: Procedure Title Section Dissolution of Plutonium Metal with Hydrochloric Acid 9.1 Dissolution of Plutonium Metal with Sulfuric Acid 9.2 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxide by the Sealed-Reflux Technique 9.3 Dissolution of Plutonium Oxide and Uranium-Plutonium Mixed Oxides by Sodium Bisulfate Fusion 9.4 Dissolution of Uranium-Plutonium Mixed Oxides and Low-Fired Plutonium Oxide in Beakers 9.5 1.3 The values stated in SI units are to be re...

American Society for Testing and Materials. Philadelphia

2008-01-01

461

EXPERIMENTAL VALIDATION OF NUCLEAR DATA AND METHODS FOR STEEL REFLECTED PLUTONIUM BURNING FAST REACTORS  

Microsoft Academic Search

There is currently considerable interest in the possibilities for fast reactors to burn plutonium. The CAPRA project has been established with the aim of determining the characteristics of plutonium and minor actinide burning cores. One major core design feature used to achieve net plutonium burning is the removal of breeder blankets and their replacement by steel reflectors. This modification creates

G. Rimpault; M. Martini; R. Jacqmin; J. C. Bosq; P. J. Finck; S. Pelloni; O. P. Joneja; A. Ziver; A. Luethi; A. Stanculescu; P. Smith

462

Estimation of plutonium in Hanford Site waste tanks based on historical records  

Microsoft Academic Search

An estimation of plutonium in the Hanford Site waste storage tanks is important to nuclear criticality concerns. A reasonable approach for estimating the plutonium in the tanks can be established by considering the recovery efficiency of the chemical separation plants on the plutonium produced in the Hanford reactors. The waste loss from the separation processes represents the bulk of the

V. E. Roetman; S. P. Roblyer; H. Toffer

1994-01-01

463

Ultraslow Wave Nuclear Burning of Uranium-Plutonium Fissile Medium on Epithermal Neutrons  

E-print Network

For a fissile medium, originally consisting of uranium-238, the investigation of fulfillment of the wave burning criterion in a wide range of neutron energies is conducted for the first time, and a possibility of wave nuclear burning not only in the region of fast neutrons, but also for cold, epithermal and resonance ones is discovered for the first time. For the first time the results of the investigation of the Feoktistov criterion fulfillment for a fissile medium, originally consisting of uranium-238 dioxide with enrichments 4.38%, 2.00%, 1.00%, 0.71% and 0.50% with respect to uranium-235, in the region of neutron energies 0.015-10.0eV are presented. These results indicate a possibility of ultraslow wave neutron-nuclear burning mode realization in the uranium-plutonium media, originally (before the wave initiation by external neutron source) having enrichments with respect to uranium-235, corresponding to the subcritical state, in the regions of cold, thermal, epithermal and resonance neutrons. In order to validate the conclusions, based on the slow wave neutron-nuclear burning criterion fulfillment depending on the neutron energy, the numerical modeling of ultraslow wave neutron-nuclear burning of a natural uranium in the epithermal region of neutron energies (0.1-7.0eV) was conducted for the first time. The presented simulated results indicate the realization of the ultraslow wave neutron-nuclear burning of the natural uranium for the epithermal neutrons.

V. D. Rusov; V. A. Tarasov; M. V. Eingorn; S. A. Chernezhenko; A. A. Kakaev; V. M. Vashchenko; M. E. Beglaryan

2014-09-29

464

Ultraslow Wave Nuclear Burning of Uranium-Plutonium Fissile Medium on Epithermal Neutrons  

E-print Network

For a fissile medium, originally consisting of uranium-238, the investigation of fulfillment of the wave burning criterion in a wide range of neutron energies is conducted for the first time, and a possibility of wave nuclear burning not only in the region of fast neutrons, but also for cold, epithermal and resonance ones is discovered for the first time. For the first time the results of the investigation of the Feoktistov criterion fulfillment for a fissile medium, originally consisting of uranium-238 dioxide with enrichments 4.38%, 2.00%, 1.00%, 0.71% and 0.50% with respect to uranium-235, in the region of neutron energies 0.015-10.0eV are presented. These results indicate a possibility of ultraslow wave neutron-nuclear burning mode realization in the uranium-plutonium media, originally (before the wave initiation by external neutron source) having enrichments with respect to uranium-235, corresponding to the subcritical state, in the regions of cold, thermal, epithermal and resonance neutrons. In order to...

Rusov, V D; Eingorn, M V; Chernezhenko, S A; Kakaev, A A

2014-01-01

465

Application of molten salt oxidation for the minimization and recovery of plutonium-238 contaminated wastes  

SciTech Connect

This paper presents the technical and economic feasibility of molten salt oxidation technology as a volume reduction and recovery process for {sup 238}Pu contaminated waste. Combustible low-level waste material contaminated with {sup 238}Pu residue is destroyed by oxidation in a 900 C molten salt reaction vessel. The combustible waste is destroyed creating carbon dioxide and steam and a small amount of ash and insoluble {sup 2328}Pu in the spent salt. The valuable {sup 238}Pu is recycled using aqueous recovery techniques. Experimental test results for this technology indicate a plutonium recovery efficiency of 99%. Molten salt oxidation stabilizes the waste converting it to a non-combustible waste. Thus installation and use of molten salt oxidation technology will substantially reduce the volume of {sup 238}Pu contaminated waste. Cost-effectiveness evaluations of molten salt oxidation indicate a significant cost savings when compared to the present plans to package, or re-package, certify and transport these wastes to the Waste Isolation Pilot Plant for permanent disposal. Clear and distinct cost advantages exist for MSO when the monetary value of the recovered {sup 238}Pu is considered.

Wishau, R.; Ramsey, K.B.; Montoya, A.

1998-12-31

466

Low impact plutonium glovebox D&D  

SciTech Connect

A dilemma often encountered in decontamination and decommissioning operations is the lack of choice as to the location where the work is to be performed. Facility siting, laboratory location, and adjacent support areas were often determined based on criteria, which while appropriate at the time, are not always the most conducive to a D&D project. One must learn to adapt and cope with as found conditions. High priority research activities, which cannot be interrupted, may be occurring in adjacent non-radiological facilities in the immediate vicinity where highly contaminated materials must be handled in the course of a D&D operation. The execution of a project within such an environment involves a high level of coordination, cooperation, professionalism and flexibility among the project, the work force and the surrounding occupants. Simply moving occupants from the potentially affected area is not always an option and much consideration must be given in the selection of the D&D methodology to be employed and the processes to be implemented. Determining project boundaries and the ensuring that adjacent occupants are included in the planning/scheduling of specific operations which impact their work area are important in the development of the safety envelope. Such was the case in the recent D&D of 61 gloveboxes contaminated with plutonium and other transuranic nuclides at the Argonne National Laboratory-East site. The gloveboxes, which were used in Department of Energy research and development program activities over the past 30 years, were decontaminated to below transuranic waste criteria, size reduced, packaged and removed from Building 212 by Argonne National Laboratory personnel in conjunction with Nuclear Fuel Services, Inc. with essentially no impact to adjacent occupants.

Rose, R.W.

1995-12-31

467

Plutonium (III) and uranium (III) nitrile complexes  

SciTech Connect

Iodine oxidation of uranium and plutonium metals in tetrahydrofuran and pyridine form AnI{sub 3}(THF){sub 4} and AnI{sub 3}(py){sub 4} (An = Pu, U). These compounds represent convenient entries Into solution An(III) chemistry in organic solvents. Extensions of the actinide metal oxidation methodology in nitrile solvents by I{sub 2}, AgPF{sub 6}, and TIPF{sub 6} are presented here. Treatment of Pu{sup 0} in acetonitrile with iodine yields a putative PuI{sub 3}(NCMe){sub x} intermediate which can be trapped with the tripodal nitrogen donor ligand tpza (tpza = (tris[(2-pyrazinyl)methyl]amine)) and forms the eight-coordinate complex (tpza)PuI{sub 3}(NCMe). Treatment of excess U{sup 0} metal by iodine in acetonitrile afforded a brown crystalline mixed valence complex, [U(NCMe){sub 9}][UI{sub 6}][I], instead of UI{sub 3}(NCMe){sub 4}. The analogous reaction in bezonitrile forms red crystalline UI{sub 4}(NCPh){sub 4}. In contrast, treatment of UI{sub 3}(THF){sub 4} with excess acetonitrile cleanly generates [U(NCMe){sub 9}][I]{sub 3}. Oxidation of Pu{sup 0} by either TI(I) or Ag(I) hexafluorophosphate salts generates a nine-coordinate homoleptic acetonitrile adduct [Pu(NCMe){sub 9}][PF{sub 6}]{sub 3}. Attempts to oxidize U{sub 0} with these salts were unsuccessful.

Enriquez, A. E. (Alejandro E.); Matonic, J. H. (John H.); Scott, B. L. (Brian L.); Neu, M. P. (Mary P.)

2002-01-01

468

Plutonium sorption and desorption behavior on bentonite.  

PubMed

Understanding plutonium (Pu) sorption to, and desorption from, mineral phases is key to understanding its subsurface transport. In this work we study Pu(IV) sorption to industrial grade FEBEX bentonite over the concentration range 10(-7)-10(-16) M to determine if sorption at typical environmental concentrations (?10(-12) M) is the same as sorption at Pu concentrations used in most laboratory experiments (10(-7)-10(-11) M). Pu(IV) sorption was broadly linear over the 10(-7)-10(-16) M concentration range during the 120 d experimental period; however, it took up to 100 d to reach sorption equilibrium. At concentrations ?10(-8) M, sorption was likely affected by additional Pu(IV) precipitation/polymerization reactions. The extent of sorption was similar to that previously reported for Pu(IV) sorption to SWy-1 Na-montmorillonite over a narrower range of Pu concentrations (10(-11)-10(-7) M). Sorption experiments with FEBEX bentonite and Pu(V) were also performed across a concentration range of 10(-11)-10(-7) M and over a 10 month period which allowed us to estimate the slow apparent rates of Pu(V) reduction on a smectite-rich clay. Finally, a flow cell experiment with Pu(IV) loaded on FEBEX bentonite demonstrated continued desorption of Pu over a 12 day flow period. Comparison with a desorption experiment performed with SWy-1 montmorillonite showed a strong similarity and suggested the importance of montorillonite phases in controlling Pu sorption/desorption reactions on FEBEX bentonite. PMID:25574607

Begg, James D; Zavarin, Mavrik; Tumey, Scott J; Kersting, Annie B

2015-03-01

469

Plutonium-238 Transuranic Waste Decision Analysis  

SciTech Connect

Five transuranic (TRU) waste sites in the Department of Energy (DOE) complex, collectively, have more than 2,100 cubic meters of Plutonium-238 (Pu-238) TRU waste that exceed the wattage restrictions of the Transuranic Package Transporter-II (TRUPACT-11). The Waste Isolation Pilot Plant (WIPP) is being developed by the DOE as a repository for TRU waste. With the Waste Isolation Pilot Plant (WIPP) opening in 1999, these sites are faced with a need to develop waste management practices that will enable the transportation of Pu-238 TRU waste to WIPP for disposal. This paper describes a decision analysis that provided a logical framework for addressing the Pu-238 TRU waste issue. The insights that can be gained by performing a formalized decision analysis are multifold. First and foremost, the very process. of formulating a decision tree forces the decision maker into structured, logical thinking where alternatives can be evaluated one against the other using a uniform set of criteria. In the process of developing the decision tree for transportation of Pu-238 TRU waste, several alternatives were eliminated and the logical order for decision making was discovered. Moreover, the key areas of uncertainty for proposed alternatives were identified and quantified. The decision analysis showed that the DOE can employ a combination approach where they will (1) use headspace gas analyses to show that a fraction of the Pu-238 TRU waste drums are no longer generating hydrogen gas and can be shipped to WIPP ''as-is'', (2) use drums and bags with advanced filter systems to repackage Pu-238 TRU waste drums that are still generating hydrogen, and (3) add hydrogen getter materials to the inner containment vessel of the TRUPACT-11to relieve the build-up of hydrogen gas during transportation of the Pu-238 TRU waste drums.

Brown, Mike; Lechel, David J.; Leigh, C.D.

1999-06-29

470

Thermal Cycling on Fatigue Failure of the Plutonium Vitrification Melter  

SciTech Connect

One method for disposition of excess plutonium is vitrification into cylindrical wasteforms. Due to the hazards of working with plutonium, the vitrification process must be carried out remotely in a shielded environment. Thus, the equipment must be easily maintained. With their simple design, induction melters satisfy this criterion, making them ideal candidates for plutonium vitrification. However, due to repeated heating and cooling cycles and differences in coefficients of thermal expansion of contacting materials fatigue failure of the induction melter is of concern. Due to the cost of the melter, the number of cycles to failure is critical. This paper presents a method for determining the cycles to failure for an induction melter by using the results from thermal and structural analyses as input to a fatigue failure model.

Jordan, Jeffrey; Gorczyca, Jennifer

2009-02-11

471

SELECTION OF SURPLUS PLUTONIUM MATERIALS FOR DISPOSITION TO WIPP  

SciTech Connect

The U.S. Department of Energy (DOE) is preparing a Surplus Plutonium Disposition (SPD) Supplemental Environmental Impact Statement (SEIS). Included in the evaluation are up to 6 metric tons (MT) of plutonium in the form of impure oxides and metals for which a disposition plan has not been decided, among options that include preparation as feed for the Mixed Oxide Fuel Fabrication Facility; disposing to high-level waste through the Savannah River Site (SRS) HB Line and H Canyon; can-in-canister disposal using the SRS Defense Waste Processing Facility; and preparation for disposal at the Waste Isolation Pilot Plant (WIPP). DOE and SRS have identified at least 0.5 MT of plutonium that, because of high levels of chemical and isotopic impurities, is impractical for disposition by methods other than the WIPP pathway. Characteristics of these items and the disposition strategy are discussed.

Allender, J.; Mcclard, J.; Christopher, J.

2012-06-08

472

Oxidation kinetics of plutonium in air: Consequences for environmental dispersal  

SciTech Connect

Kinetic studies show that plutonium corrosion in air is catalyzed by plutonium hydride on the metal surface and suggest that the process has caused storage containers to fail. The catalyzed reaction initiates at 25{degrees}C, indiscriminately consumes both O{sub 2} and N{sub 2}, and transforms metal into a dispersible product at a 10{sup 7}-10{sup 10} faster rate (0.6 {+-} 0.1 g Pu/cm{sup 2} min) than normal air oxidation. The catalyzed Pu+O{sub 2} reaction advances into the metal at a linear rate of 2.9 m/h. Rate equations and particle size data, which are presented for catalyzed and atmospheric corrosion at temperatures up to 3500{degrees}C, provide a technical basis for more accurately assessing the dispersal hazard posed by plutonium metal.

Haschke, J.M.; Allen, T.H.; Martz, J.C.

1997-09-01

473

Extraction of Uranium, Neptunium and Plutonium from Caustic Media  

SciTech Connect

5 Fundamental research on uranium, neptunium and plutonium separation from alkaline media using solvent extraction is being conducted. Specific extractants for these actinides from alkaline media have been synthesized to investigate the feasibility of selective removal of these elements. Two families of extractants have been studied: terephthalamide and tetra(hydroxybenzyl)ethylene diamine derivatives. Fundamental studies were conducted to characterize their extraction behavior from a wide variety of aqueous conditions. The terephthalamide derivatives exhibit a significant extraction strength along with a discriminatory behavior among the actinides, plutonium being extracted the most strongly. Quantitative extraction of plutonium and moderate extraction of neptunium and uranium was achieved from a simple caustic solution. Interestingly, strontium is also quantitatively extracted by these derivatives. However, their stability to highly caustic solutions still needs to be imp roved. Tetra(hydroxybenzyl)ethylene diamine derivatives exhibit a very good stability to caustic conditions and are currently being studied.

Delmau, Laetitia H.; Bonnesen, Peter V.; Engle, Nancy L.; Raymond, Kenneth N.; Xu, Jade

2004-03-28

474

Isotopic Measurements: Interpretation and Implications of Plutonium Data  

SciTech Connect

One of the fundamental activities within the field of nuclear forensics is the laboratory analysis of nuclear material; one aspect is providing the isotopic composition of the material under investigation. For both plutonium and uranium, this includes a unique suite of isotopes that, individually and collectively (i.e. an isotopic vector), will help characterize these materials, and potentially provide insight into their mode of production, intended utilization, and processing history. A full understanding of how this information is used provides the basis for defining the need for these measurements and helps determine the precision and accuracy requirements for those measurements. This paper provides an overview of this process as it applies to plutonium, discussing how reactor design and operating parameters can impact the resultant plutonium vector, thereby giving us the ability to infer those reactor traits based on isotopic measurements.

Luksic, Andrzej T.; Collins, Brian A.; Friese, Judah I.; Schwantes, Jon M.; Starner, Jason R.; Wacker, John F.

2010-08-11

475

MICROBIAL TRANSFORMATIONS OF PLUTONIUM AND IMPLICATIONS FOR ITS MOBILITY.  

SciTech Connect

The current state of knowledge of the effect of plutonium on microorganisms and microbial activity is reviewed, and also the microbial processes affecting its mobilization and immobilization. The dissolution of plutonium is predominantly due to their production of extracellular metabolic products, organic acids, such as citric acid, and sequestering agents, such as siderophores. Plutonium may be immobilized by the indirect actions of microorganisms resulting in changes in Eh and its reduction from a higher to lower oxidation state, with the precipitation of Pu, its bioaccumulation by biomass, and bioprecipitation reactions. In addition, the abundance of microorganisms in Pu-contaminated soils, wastes, natural analog sites, and backfill materials that will be used for isolating the waste and role of microbes as biocolloids in the transport of Pu is discussed.

FRANCIS, A.J.

2000-09-30

476

A perspective on safeguarding and monitoring of excess military plutonium  

SciTech Connect

The purpose of this paper is to provide a perspective and framework for the development of safeguarding and monitoring procedures for the various stages of disposition of excess military plutonium. The paper briefly outlines and comments on some of the issues involved in safeguarding and monitoring excess military plutonium as it progresses from weapons through dismantlement, to fabrication as reactor fuel, to use in a reactor, and finally to storage and disposal as spent fuel. {open_quotes}Military{close_quotes} refers to ownership, and includes both reactor-grade and weapon-grade plutonium. {open_quotes}Excess{close_quotes} refers to plutonium (in any form) that a government decides is no longer needed for military use and can be irrevocably removed from military stockpiles. Many of the issues and proposals presented in this paper are based on, or are similar to, those mentioned in the National Academy of Sciences (NAS) report on excess military plutonium. Safeguards for plutonium disposition are discussed elsewhere in terms of requirements established by the U.S. Department of Energy (DOE), the U.S. Nuclear Regulatory Commission (NRC), and the International Atomic Energy Agency (IAEA). Here, the discussion is less specific. The term {open_quotes}safeguarding{close_quotes} is used broadly to refer to materials control and accountancy (MC&A), containment and surveillance (C&S), and physical protection of nuclear materials by the state that possesses those materials. This is also referred to as material protection, control, and accountancy (MPCA). The term {open_quotes}safeguarding{close_quotes} was chosen for brevity and to distinguish MPCA considered in this paper from international or IAEA safeguards. {open_quotes}Monitoring{close_quotes} is used to refer to activities designed to assure another party (state or international organization) that the nuclear materials of the host state (the United States or Russia) are secure and not subject to unauthorized use.

Sutcliffe, W.G.

1994-10-02

477

Integrated development and testing plan for the plutonium immobilization project  

SciTech Connect

This integrated plan for the DOE Office of Fissile Materials Disposition (MD) describes the technology development and major project activities necessary to support the deployment of the immobilization approach for disposition of surplus weapons-usable plutonium. The plan describes details of the development and testing (D&T) tasks needed to provide technical data for design and operation of a plutonium immobilization plant based on the ceramic can-in-canister technology (''Immobilization Fissile Material Disposition Program Final Immobilization Form Assessment and Recommendation'', UCRL-ID-128705, October 3, 1997). The plan also presents tasks for characterization and performance testing of the immobilization form to support a repository licensing application and to develop the basis for repository acceptance of the plutonium form. Essential elements of the plant project (design, construction, facility activation, etc.) are described, but not developed in detail, to indicate how the D&T results tie into the overall plant project. Given the importance of repository acceptance, specific activities to be conducted by the Office of Civilian Radioactive Waste Management (RW) to incorporate the plutonium form in the repository licensing application are provided in this document, together with a summary of how immobilization D&T activities provide input to the license activity. The ultimate goal of the Immobilization Project is to develop, construct, and operate facilities that will immobilize from about 18 to 50 tonnes (MT) of U.S. surplus weapons usable plutonium materials in a manner that meets the ''spent fuel'' standard (Fissile Materials Storage and Disposition Programmatic Environmental Impact Statement Record of Decision, ''Storage and Disposition Final PEIS'', issued January 14, 1997, 62 Federal Register 3014) and is acceptable for disposal in a geologic repository. In the can-in-canister technology, this is accomplished by encapsulating the plutonium-containing ceramic forms within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2006 and be completed within 10 years.

Kan, T.

1998-07-01

478

Curium analysis in plutonium uranium mixed oxide by x-ray fluorescence and absorption fine structure spectroscopy.  

PubMed

Plutonium uranium mixed oxide (MOX) fuels are being used in commercial nuclear reactors. The actinides in these fuels need to be analyzed after irradiation for assessing their behaviour with regards to their environment and the coolant. In this work the study of the local occurrence, speciation and next-neighbour environment of curium (Cm) in the (Pu,U)O2 lattice within an irradiated (60 MW d kg(-1) average burn-up) MOX sample was performed employing micro-x-ray fluorescence (µ-XRF) and micro-x-ray absorption fine structure (µ-XAFS) spectroscopy. The chemical bonds, valences and stoichiometry of Cm (? 0.7 wt% in the rim and ? 0.03 wt% in the centre) are determined from the experimental data gained for the irradiated fuel material examined in its centre and peripheral (rim) zones of the fuel. Curium occurrence is also reduced from the centre (hot) to the periphery (colder) because of the condensation of these volatile oxides. In the irradiated sample Cm builds up as Cm(3+) species (>90%) within a [CmO8](13-) or [CmO7](11-) coordination environment and no (<10%) Cm(IV) can be detected in the rim zone. Curium dioxide is reduced because of the redox buffering activity of the uranium dioxide matrix and of its thermodynamic instability. PMID:24054692

Degueldre, C; Borca, C; Cozzo, C

2013-10-15

479

Experience With Chlorine Dioxide in Brussels: Generation of Chlorine Dioxide  

Microsoft Academic Search

The yield of chlorine dioxide (ClO?) is influenced by chemical conditions (e.g., initial chlorine concentration, alkalinity) and by reactor design (e.g., detention time, method for mixing chemicals). This article describes the design and operation of ClO?-generating systems used by the Brussels' Intercommunal Waterboard. Improved reactor designs have increased ClO? yields from 65-80 percent to > 95 percent of the theoretical

W. J. Masschelein

1984-01-01

480

Plutonium management: A fuel supplier`s perspective  

SciTech Connect

British Nuclear Fuels plc has over 40 yr of experience in providing nuclear fuel cycle services to its utility customers worldwide. These services include the reprocessing of spent fuel and the manufacture of mixed-oxide (MOX) fuel from plutonium separated in the reprocessing campaign and the vitrification of the high-level waste (HLW) by-products of the reprocessing activities. This experience is directly and immediately applicable to the needs of the United States and the former Soviet Union as both nations grapple with the dilemma of how to safely and securely manage and dispose of more than 100 t of excess weapons-grade plutonium.

Meigs, M.F. [BNFL, Inc., Washington, DC (United States)

1995-12-31

481

Elemental composition in sealed plutonium-beryllium neutron sources.  

PubMed

Five sealed plutonium-beryllium (PuBe) neutron sources from various manufacturers were disassembled. Destructive chemical analyses for recovered PuBe materials were conducted for disposition purposes. A dissolution method for PuBe alloys was developed for quantitative plutonium (Pu) and beryllium (Be) assay. Quantitation of Be and trace elements was performed using plasma based spectroscopic instruments, namely inductively coupled plasma mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES). Pu assay was accomplished by an electrochemical method. Variations in trace elemental contents among the five PuBe sources are discussed. PMID:25464182

Xu, N; Kuhn, K; Gallimore, D; Martinez, A; Schappert, M; Montoya, D; Lujan, E; Garduno, K; Tandon, L

2014-10-22

482

Plutonium: Aging mechanisms and weapon pit lifetime assessment  

NASA Astrophysics Data System (ADS)

Planning for future refurbishment and manufacturing needs of the U.S. nuclear weapons complex critically depends on credible estimates for component lifetimes. One of the most important of these components is the pit, that portion of the weapon that contains the fissile element plutonium. The U.S. government has proposed construction of a new Modern Pit Facility, and a key variable in planning both the size and schedule for this facility is the minimum estimated lifetime for stockpile pits. This article describes the current understanding of aging effects in plutonium, provides a lifetime estimate range, and outlines in some detail methodology that will improve this estimate over the next few years.

Martz, Joseph C.; Schwartz, Adam J.

2003-09-01

483

Selective Extraction of Uranium from Liquid or Supercritical Carbon Dioxide  

SciTech Connect

Current liquid-liquid extraction processes used in recycling irradiated nuclear fuel rely on (1) strong nitric acid to dissolve uranium oxide fuel, and (2) the use of aliphatic hydrocarbons as a diluent in formulating the solvent used to extract uranium. The nitric acid dissolution process is not selective. It dissolves virtually the entire fuel meat which complicates the uranium extraction process. In addition, a solvent washing process is used to remove TBP degradation products, which adds complexity to the recycling plant and increases the overall plant footprint and cost. A liquid or supercritical carbon dioxide (l/sc -CO2) system was designed to mitigate these problems. Indeed, TBP nitric acid complexes are highly soluble in l/sc -CO2 and are capable of extracting uranium directly from UO2, UO3 and U3O8 powders. This eliminates the need for total acid dissolution of the irradiated fuel. Furthermore, since CO2 is easily recycled by evaporation at room temperature and pressure, it eliminates the complex solvent washing process. In this report, we demonstrate: (1) A reprocessing scheme starting with the selective extraction of uranium from solid uranium oxides into a TBP-HNO3 loaded Sc-CO2 phase, (2) Back extraction of uranium into an aqueous phase, and (3) Conversion of recovered purified uranium into uranium oxide. The purified uranium product from step 3 can be disposed of as low level waste, or mixed with enriched uranium for use in a reactor for another fuel cycle. After an introduction on the concept and properties of supercritical fluids, we first report the characterization of the different oxides used for this project. Our extraction system and our online monitoring capability using UV-Vis absorbance spectroscopy directly in sc-CO2 is then presented. Next, the uranium extraction efficiencies and kinetics is demonstrated for different oxides and under different physical and chemical conditions: l/sc -CO2 pressure and temperature, TBP/HNO3 complex used, reductant or complexant used for selectivity, and ionic liquids used as supportive media. To complete the extraction and recovery cycle, we then demonstrate uranium back extraction from the TBP loaded sc-CO2 phase into an aqueous phase and the characterization of the uranium complex formed at the end of this process. Another aspect of this project was to limit proliferation risks by either co-extracting uranium and plutonium, or by leaving plutonium behind by selectively extracting uranium. We report that the former is easily achieved, since plutonium is in the tetravalent or hexavalent oxidation state in the oxidizing environment created by the TBP-nitric acid complex, and is therefore co-extracted. The latter is more challenging, as a reductant or complexant to plutonium has to be used to selectively extract uranium. After undertaking experiments on different reducing or complexing systems (e.g., AcetoHydroxamic Acid (AHA), Fe(II), ascorbic acid), oxalic acid was chosen as it can complex tetravalent actinides (Pu, Np, Th) in the aqueous phase while allowing the extraction of hexavalent uranium in the sc-CO2 phase. Finally, we show results using an alternative media to commonly used aqueous phases: ionic liquids. We show the dissolution of uranium in ionic liquids and its extraction using sc-CO2 with and without the presence of AHA. The possible separation of trivalent actinides from uranium is also demonstrated in ionic liquids using neodymium as a surrogate and diglycolamides as the extractant.

Farawila, Anne F.; O'Hara, Matthew J.; Wai, Chien M.; Taylor, Harry Z.; Liao, Yu-Jung

2012-07-31

484

SMALL-SCALE TESTING OF PLUTONIUM (IV) OXALATE PRECIPITATION AND CALCINATION TO PLUTONIUM OXIDE TO SUPPORT THE MOX FEED MISSION  

SciTech Connect

The H-Canyon facility will be used to dissolve Pu metal for subsequent purification and conversion to plutonium dioxide (PuO{sub 2}) using Phase II of HB-Line. To support the new mission, SRNL conducted a series of experiments to produce calcined plutonium (Pu) oxide and measure the physical properties and water adsorption of that material. This data will help define the process operating conditions and material handling steps for HB-Line. An anion exchange column experiment produced 1.4 L of a purified 52.6 g/L Pu solution. Over the next nine weeks, seven Pu(IV) oxalate precipitations were performed using the same stock Pu solution, with precipitator feed acidities ranging from 0.77 M to 3.0 M nitric acid and digestion times ranging from 5 to 30 minutes. Analysis of precipitator filtrate solutions showed Pu losses below 1% for all precipitations. The four larger precipitation batches matched the target oxalic acid addition time of 44 minutes within 4 minutes. The three smaller precipitation batches focused on evaluation of digestion time and the oxalic acid addition step ranged from 25-34 minutes because of pump limitations in the low flow range. Following the precipitations, 22 calcinations were performed in the range of 610-690 C, with the largest number of samples calcined at either 650 or 635 C. Characterization of the resulting PuO{sub 2} batches showed specific surface areas in the range of 5-14 m{sup 2}/g, with 16 of the 22 samples in the range of 5-10 m2/g. For samples analyzed with typical handling (exposed to ambient air for 15-45 minutes with relative humidities of 20-55%), the moisture content as measured by Mass Spectrometry ranged from 0.15 to 0.45 wt % and the total mass loss at 1000 C, as measured by TGA, ranged from 0.21 to 0.58 wt %. For the samples calcined between 635 and 650 C, the moisture content without extended exposure ranged from 0.20 to 0.38 wt %, and the TGA mass loss ranged from 0.26 to 0.46 wt %. Of these latter samples, the samples calcined at 650 C generally had lower specific surface areas and lower moisture contents than the samples calcined at 635 C, which matches expectations from the literature. Taken together, the TGA-MS results for samples handled at nominally 20-50% RH, without extended exposure, indicate that the Pu(IV) oxalate precipitation process followed by calcination at 635-650 C appears capable of producing PuO{sub 2} with moisture content < 0.5 wt% as required by the 3013 Standard. Exposures of PuO{sub 2} samples to ambient air for 3 or more hours generally showed modest mass gains that were primarily gains in moisture content. These results point to the need for a better understanding of the moisture absorption of PuO{sub 2} and serve as a warning that extended exposure times, particularly above the 50% RH level observed in this study will make the production of PuO{sub 2} with less than 0.5 wt % moisture more challenging. Samples analyzed in this study generally contained approximately 2 monolayer equivalents of moisture. In this study, the bulk of the moisture released from samples below 300 C, as did a significant portion of the CO{sub 2}. Samples in this study consistently released a minor amount of NO in the 40-300 C range, but no samples released CO or SO{sub 2}. TGA-MS results also showed that MS moisture content accounted for 80 {+-} 8% of the total mass loss at 1000 C measured by the TGA. The PuO{sub 2} samples produced had particles sizes that typically ranged from 0.2-88 {micro}m, with the mean particle size ranging from 6.4-9.3 {micro}m. The carbon content of ten different calcination batches ranged from 190-480 {micro}g C/g Pu, with an average value of 290 {micro}g C/g Pu. A statistical review of the calcination conditions and resulting SSA values showed that in both cases tested, calcination temperature had a significant effect on SSA, as expected from literature data. The statistical review also showed that batch size had a significant effect on SSA, but the narrow range of batch sizes tested is a compelling reason to set aside that result until tests

Crowder, M.; Pierce, R.; Scogin, J.; Daniel, G.; King, W.

2012-06-25

485

Proceedings of the Plutonium Futures ? The Science 2006 Conference  

SciTech Connect

Plutonium Futures--The Science 2006 provided opportunities to examine present knowledge of the chemical and physical properties of plutonium and other actinides in complex media and materials; to discuss the current and emerging science (chemistry, physics, materials science, nuclear science, and environmental effects) of plutonium and actinides relevant to enhancing global nuclear security; and to exchange ideas. This international conference also provided a forum for illustrating and enhancing capabilities and interests, and assessing issues in these areas. U.S. and international scientists, engineers, faculty, and students from universities, national laboratories, and DOE's nuclear complex were encouraged to participate and make technical contributions. The Conference ran from Sunday, July 9th through Thursday, July 13th. A popular aspect of the conference was the opening tutorial session on Sunday afternoon intended for students and scientists new to the area of plutonium research. The tutorial was well attended by novices and veterans alike, and featured such diverse topics as; plutonium metallurgy, plutonium in the environment, and international arms control and nonproliferation. Two plenary lectures began each morning and each afternoon session and highlighted the breakout sessions on coordination/organometallic chemistry, solid-state physics, environmental chemistry, materials science, separations and reprocessing, advanced fuels and waste forms, phase transformations, solution and gas-phase chemistry, compounds and complexes, electronic structure and physical properties, and more. Chemistry Highlights--Among the many chemistry highlights presented in this proceedings are the overview of concepts and philosophies on inert nuclear fuel matrices and concerns about the ever-increasing amounts of minor actinides and plutonium generated in the fuel cycle. The various ideas involve multiple reduction schemes for these materials, suggesting fuels for 'burning' or 'cradle-to-grave' accountability for various reactor types. Related work is presented on identification of the unique reaction mechanisms and identification of the intermediate products, including Pu(III), at the end of the PUREX process. In the important area of nuclear forensics, actual scenarios of nuclear materials confiscation and the successes of applying forensics protocols to determine attribution and possible intention are provided. In the area of reactor incidents, there is no other place on Earth like the Chernobyl Site Object Shelter and radioactive aerosol particle characterization studies reflect an important effort described herein. An additional report from another unique environmental site presents results on radionuclide monitoring, fate, and transport in the ecosystem of the Yenisei River in the Krasoyarsk region. In the area of nuclear waste disposal, a study of the ion irradiation damage to pyrochlore compounds with varying amounts of host elements and actinide dopants is presented. Papers on both the aqueous and nonaqueous chemistry of plutonium and other actinides are presented including anhydrous coordination chemistry and redox behavior in the presence of humic materials and the their sorption on common minerals in the environment. Also published herein are reports on the field of anhydrous coordination chemistry of the transuranic elements where there is scarce information. Solid-State and Materials Highlights--Plutonium solid-state and materials research is represented in these proceedings by a wealth of leading edge discovery class research. The breadth of this research is reflected in the topics covered: solid-state; materials science; superconductivity; phase changes, phonons, and entropy; electronic structure and physical properties; surface science and corrosion; and radiation effects, defects, impurities, and property changes. Indeed the scientific challenge and excitement of plutonium can best be highlighted by quoting the tutorial prospectus of Drs. Sarrao and Schwartz. 'Plutonium has long been recognized as a complex and scie

Fluss, M; Hobart, D; Allan, P; Jarvinen, G

2007-07-12

486

Electrochemically regenerable carbon dioxide absorber  

NASA Technical Reports Server (NTRS)

Preliminary designs were generated for two electrochemically regenerable carbon dioxide absorber concepts. Initially, an electrochemically regenerable absorption bed concept was designed. This concept incorporated the required electrochemical regeneration components in the absorber design, permitting the absorbent to be regenerated within the absorption bed. This hardware was identified as the electrochemical absorber hardware. The second hardware concept separated the functional components of the regeneration and absorption process. This design approach minimized the extravehicular activity component volume by eliminating regeneration hardware components within the absorber. The electrochemical absorber hardware was extensively characterized for major operating parameters such as inlet carbon dioxide partial pressure, process air flow rate, operational pressure, inlet relative humidity, regeneration current density and absorption/regeneration cycle endurance testing.

Woods, R. R.; Marshall, R. D.; Schubert, F. H.; Heppner, D. B.

1979-01-01

487

Oxygen and carbon dioxide sensing  

NASA Technical Reports Server (NTRS)

A high electron mobility transistor (HEMT) capable of performing as a CO.sub.2 or O.sub.2 sensor is disclosed, hi one implementation, a polymer solar cell can be connected to the HEMT for use in an infrared detection system. In a second implementation, a selective recognition layer can be provided on a gate region of the HEMT. For carbon dioxide sensing, the selective recognition layer can be, in one example, PEI/starch. For oxygen sensing, the selective recognition layer can be, in one example, indium zinc oxide (IZO). In one application, the HEMTs can be used for the detection of carbon dioxide and oxygen in exhaled breath or blood.

Ren, Fan (Inventor); Pearton, Stephen John (Inventor)

2012-01-01

488

Molecular Structure of Nitrogen dioxide  

NSDL National Science Digital Library

Nitrogen dioxide is a brown gas that readily dimerizes at lower temperatures to form the colorless gas dinitrogen trioxide. It is a byproduct of combustion that pollutes air and its gives smog its characteristic brown color. When gasoline, diesel fuel, or coal is burned at high temperatures nitric oxide (NO) is formed. Nitric oxide reacts slowly with oxygen to form nitrogen dioxide, or it can react with many organic-oxygen containing radicals (e.g., alkoxy and peroxy radicals) found in the atmosphere (also products of combustion) to more rapidly form NO2. The photolysis of NO2 by sunlight is the only known source of ozone to the troposphere (the layer of atmosphere closest to the earth); ozone is one of the most toxic components of smog and adversely affects human, animal and plant health in densely populated polluted regions.

2002-09-11

489

Plutonium immobilization plant using glass in new facilities at the Savannah River Site  

SciTech Connect

The Plutonium Immobilization Plant (PIP) accepts plutonium (Pu) from pit conversion and from non-pit sources and, through a glass immobilization process, converts the plutonium into an immobilized form that can be disposed of in a high level waste (HLW) repository. This immobilization process is shown conceptually in Figure 1-1. The objective is to make an immobilized form, suitable for geologic disposal, in which the plutonium is as inherently unattractive and inaccessible as the plutonium in spent fuel from commercial reactors.

DiSabatino, A.

1998-06-01

490

Minutes of the 28th Annual Plutonium Sample Exchange Meeting. Part II: metal sample exchange  

SciTech Connect

Contents of this publication include the following list of participating laboratories; agenda; attendees; minutes of October 25 and 26 meeting; and handout materials supplied by speakers. The handout materials cover the following: statistics and reporting; plutonium - chemical assay 100% minus impurities; americium neptunium, uranium, carbon and iron data; emission spectroscopy data; plutonium<